ExcelJS

Read, manipulate and write spreadsheet data and styles to XLSX and JSON.

Reverse engineered from Excel spreadsheet files as a project.

Translations

• 中文文档

Installation

npm install exceljs

New Features!

Contributions

Contributions are very welcome! It helps me know what features are desired or what bugs are causing the most pain.

I have just one request; If you submit a pull request for a bugfix, please add a unit-test or integration-test (in the spec folder) that catches the problem. Even a PR that just has a failing test is fine - I can analyse what the test is doing and fix the code from that.

Note: Please try to avoid modifying the package version in a PR. Versions are updated on release and any change will most likely result in merge collisions.

To be clear, all contributions added to this library will be included in the library's MIT licence.

Contents

Importing

const ExcelJS = require('exceljs');

ES5 Imports

To use the ES5 transpiled code, use the dist/es5 path.

const ExcelJS = require('exceljs/dist/es5');

Note: The ES5 build has an implicit dependency on a number of polyfills which are no longer explicitly added by exceljs. You will need to add "core-js" and "regenerator-runtime" to your dependencies and include the following requires in your code before the exceljs import:

// polyfills required by exceljs
require('core-js/modules/es.promise');
require('core-js/modules/es.object.assign');
require('core-js/modules/es.object.keys');
require('regenerator-runtime/runtime');

// ...

const ExcelJS = require('exceljs/dist/es5');

Browserify

ExcelJS publishes two browserified bundles inside the dist/ folder:

One with implicit dependencies on core-js polyfills...

<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-polyfill/6.26.0/polyfill.js"></script>
<script src="exceljs.js"></script>

And one without...

<script src="--your-project's-pollyfills-here--"></script>
<script src="exceljs.bare.js"></script>

Interface

Create a Workbook

var workbook = new Excel.Workbook();

Set Workbook Properties

workbook.creator = 'Me';
workbook.lastModifiedBy = 'Her';
workbook.created = new Date(1985, 8, 30);
workbook.modified = new Date();
workbook.lastPrinted = new Date(2016, 9, 27);

// Set workbook dates to 1904 date system
workbook.properties.date1904 = true;

Set Calculation Properties

// Force workbook calculation on load
workbook.calcProperties.fullCalcOnLoad = true;

Workbook Views

The Workbook views controls how many separate windows Excel will open when viewing the workbook.

workbook.views = [
  {
    x: 0, y: 0, width: 10000, height: 20000,
    firstSheet: 0, activeTab: 1, visibility: 'visible'
  }
]

Add a Worksheet

var sheet = workbook.addWorksheet('My Sheet');

Use the second parameter of the addWorksheet function to specify options for the worksheet.

For Example:

// create a sheet with red tab colour
var sheet = workbook.addWorksheet('My Sheet', {properties:{tabColor:{argb:'FFC0000'}}});

// create a sheet where the grid lines are hidden
var sheet = workbook.addWorksheet('My Sheet', {views: [{showGridLines: false}]});

// create a sheet with the first row and column frozen
var sheet = workbook.addWorksheet('My Sheet', {views:[{state: 'frozen', xSplit: 1, ySplit:1}]});

Remove a Worksheet

Use the worksheet id to remove the sheet from workbook.

For Example:

// Create a worksheet
var sheet = workbook.addWorksheet('My Sheet');

// Remove the worksheet using worksheet id
workbook.removeWorksheet(sheet.id)

Access Worksheets

// Iterate over all sheets
// Note: workbook.worksheets.forEach will still work but this is better
workbook.eachSheet(function(worksheet, sheetId) {
  // ...
});

// fetch sheet by name
var worksheet = workbook.getWorksheet('My Sheet');

// fetch sheet by id
var worksheet = workbook.getWorksheet(1);

Worksheet State

// make worksheet visible
worksheet.state = 'visible';

// make worksheet hidden
worksheet.state = 'hidden';

// make worksheet hidden from 'hide/unhide' dialog
worksheet.state = 'veryHidden';

Worksheet Properties

Worksheets support a property bucket to allow control over some features of the worksheet.

// create new sheet with properties
var worksheet = workbook.addWorksheet('sheet', {properties:{tabColor:{argb:'FF00FF00'}}});

// create a new sheet writer with properties
var worksheetWriter = workbookWriter.addSheet('sheet', {properties:{outlineLevelCol:1}});

// adjust properties afterwards (not supported by worksheet-writer)
worksheet.properties.outlineLevelCol = 2;
worksheet.properties.defaultRowHeight = 15;

Supported Properties

| Name | Default | Description | | ---------------- | ---------- | ----------- | | tabColor | undefined | Color of the tabs | | outlineLevelCol | 0 | The worksheet column outline level | | outlineLevelRow | 0 | The worksheet row outline level | | defaultRowHeight | 15 | Default row height | | defaultColWidth | (optional) | Default column width | | dyDescent | 55 | TBD |

Worksheet Metrics

Some new metrics have been added to Worksheet...

| Name | Description | | ----------------- | ----------- | | rowCount | The total row size of the document. Equal to the row number of the last row that has values. | | actualRowCount | A count of the number of rows that have values. If a mid-document row is empty, it will not be included in the count. | | columnCount | The total column size of the document. Equal to the maximum cell count from all of the rows | | actualColumnCount | A count of the number of columns that have values. |

Page Setup

All properties that can affect the printing of a sheet are held in a pageSetup object on the sheet.

// create new sheet with pageSetup settings for A4 - landscape
var worksheet =  workbook.addWorksheet('sheet', {
  pageSetup:{paperSize: 9, orientation:'landscape'}
});

// create a new sheet writer with pageSetup settings for fit-to-page
var worksheetWriter = workbookWriter.addSheet('sheet', {
  pageSetup:{fitToPage: true, fitToHeight: 5, fitToWidth: 7}
});

// adjust pageSetup settings afterwards
worksheet.pageSetup.margins = {
  left: 0.7, right: 0.7,
  top: 0.75, bottom: 0.75,
  header: 0.3, footer: 0.3
};

// Set Print Area for a sheet
worksheet.pageSetup.printArea = 'A1:G20';

// Set multiple Print Areas by separating print areas with '&&'
worksheet.pageSetup.printArea = 'A1:G10&&A11:G20';

// Repeat specific rows on every printed page
worksheet.pageSetup.printTitlesRow = '1:3';

// Repeat specific columns on every printed page
worksheet.pageSetup.printTitlesColumn = 'A:C';

Supported pageSetup settings

| Name | Default | Description | | --------------------- | ------------- | ----------- | | margins | | Whitespace on the borders of the page. Units are inches. | | orientation | 'portrait' | Orientation of the page - i.e. taller (portrait) or wider (landscape) | | horizontalDpi | 4294967295 | Horizontal Dots per Inch. Default value is -1 | | verticalDpi | 4294967295 | Vertical Dots per Inch. Default value is -1 | | fitToPage | | Whether to use fitToWidth and fitToHeight or scale settings. Default is based on presence of these settings in the pageSetup object - if both are present, scale wins (i.e. default will be false) | | pageOrder | 'downThenOver'| Which order to print the pages - one of ['downThenOver', 'overThenDown'] | | blackAndWhite | false | Print without colour | | draft | false | Print with less quality (and ink) | | cellComments | 'None' | Where to place comments - one of ['atEnd', 'asDisplayed', 'None'] | | errors | 'displayed' | Where to show errors - one of ['dash', 'blank', 'NA', 'displayed'] | | scale | 100 | Percentage value to increase or reduce the size of the print. Active when fitToPage is false | | fitToWidth | 1 | How many pages wide the sheet should print on to. Active when fitToPage is true | | fitToHeight | 1 | How many pages high the sheet should print on to. Active when fitToPage is true | | paperSize | | What paper size to use (see below) | | showRowColHeaders | false | Whether to show the row numbers and column letters | | showGridLines | false | Whether to show grid lines | | firstPageNumber | | Which number to use for the first page | | horizontalCentered | false | Whether to center the sheet data horizontally | | verticalCentered | false | Whether to center the sheet data vertically |

Example Paper Sizes

| Name | Value | | ----------------------------- | --------- | | Letter | undefined | | Legal | 5 | | Executive | 7 | | A4 | 9 | | A5 | 11 | | B5 (JIS) | 13 | | Envelope #10 | 20 | | Envelope DL | 27 | | Envelope C5 | 28 | | Envelope B5 | 34 | | Envelope Monarch | 37 | | Double Japan Postcard Rotated | 82 | | 16K 197x273 mm | 119 |

Headers and Footers

Here's how to add headers and footers. The added content is mainly text, such as time, introduction, file information, etc., and you can set the style of the text. In addition, you can set different texts for the first page and even page.

Note: Images are not currently supported.

// Set footer (default centered), result: "Page 2 of 16"
worksheet.headerFooter.oddFooter = "Page &P of &N";

// Set the footer (default centered) to bold, resulting in: "Page 2 of 16"
worksheet.headerFooter.oddFooter = "Page &P of &N";

// Set the left footer to 18px and italicize. Result: "Page 2 of 16"
worksheet.headerFooter.oddFooter = "&LPage &P of &N";

// Set the middle header to gray Aril, the result: "52 exceljs"
worksheet.headerFooter.oddHeader = "&C&KCCCCCC&\"Aril\"52 exceljs";

// Set the left, center, and right text of the footer. Result: “Exceljs” in the footer left. “demo.xlsx” in the footer center. “Page 2” in the footer right
worksheet.headerFooter.oddFooter = "&Lexceljs&C&F&RPage &P";

// Add different header & footer for the first page
worksheet.headerFooter.differentFirst = true;
worksheet.headerFooter.firstHeader = "Hello Exceljs";
worksheet.headerFooter.firstFooter = "Hello World"

Supported headerFooter settings

| Name | Default | Description | | ----------------- | --------- | ----------- | | differentFirst | false | Set the value of differentFirst as true, which indicates that headers/footers for first page are different from the other pages | | differentOddEven | false | Set the value of differentOddEven as true, which indicates that headers/footers for odd and even pages are different | | oddHeader | null | Set header string for odd(default) pages, could format the string | | oddFooter | null | Set footer string for odd(default) pages, could format the string | | evenHeader | null | Set header string for even pages, could format the string | | evenFooter | null | Set footer string for even pages, could format the string | | firstHeader | null | Set header string for the first page, could format the string | | firstFooter | null | Set footer string for the first page, could format the string |

Script Commands

| Commands | Description | | ------------ | ----------- | | &L | Set position to the left | | &C | Set position to the center | | &R | Set position to the right | | &P | The current page number | | &N | The total number of pages | | &D | The current date | | &T | The current time | | &G | A picture | | &A | The worksheet name | | &F | The file name | | &B | Make text bold | | &I | Italicize text | | &U | Underline text | | &"font name" | font name, for example &"Aril" | | &font size | font size, for example 12 | | &KHEXCode | font color, for example &KCCCCCC |

Worksheet Views

Worksheets now support a list of views, that control how Excel presents the sheet:

• frozen - where a number of rows and columns to the top and left are frozen in place. Only the bottom right section will scroll
• split - where the view is split into 4 sections, each semi-independently scrollable.

Each view also supports various properties:

| Name | Default | Description | | ----------------- | --------- | ----------- | | state | 'normal' | Controls the view state - one of normal, frozen or split | | rightToLeft | false | Sets the worksheet view's orientation to right-to-left | | activeCell | undefined | The currently selected cell | | showRuler | true | Shows or hides the ruler in Page Layout | | showRowColHeaders | true | Shows or hides the row and column headers (e.g. A1, B1 at the top and 1,2,3 on the left | | showGridLines | true | Shows or hides the gridlines (shown for cells where borders have not been defined) | | zoomScale | 100 | Percentage zoom to use for the view | | zoomScaleNormal | 100 | Normal zoom for the view | | style | undefined | Presentation style - one of pageBreakPreview or pageLayout. Note pageLayout is not compatible with frozen views |

Frozen Views

Frozen views support the following extra properties:

| Name | Default | Description | | ----------------- | --------- | ----------- | | xSplit | 0 | How many columns to freeze. To freeze rows only, set this to 0 or undefined | | ySplit | 0 | How many rows to freeze. To freeze columns only, set this to 0 or undefined | | topLeftCell | special | Which cell will be top-left in the bottom-right pane. Note: cannot be a frozen cell. Defaults to first unfrozen cell |

worksheet.views = [
  {state: 'frozen', xSplit: 2, ySplit: 3, topLeftCell: 'G10', activeCell: 'A1'}
];

Split Views

Split views support the following extra properties:

| Name | Default | Description | | ----------------- | --------- | ----------- | | xSplit | 0 | How many points from the left to place the splitter. To split vertically, set this to 0 or undefined | | ySplit | 0 | How many points from the top to place the splitter. To split horizontally, set this to 0 or undefined | | topLeftCell | undefined | Which cell will be top-left in the bottom-right pane. | | activePane | undefined | Which pane will be active - one of topLeft, topRight, bottomLeft and bottomRight |

worksheet.views = [
  {state: 'split', xSplit: 2000, ySplit: 3000, topLeftCell: 'G10', activeCell: 'A1'}
];

Auto filters

It is possible to apply an auto filter to your worksheet.

worksheet.autoFilter = 'A1:C1';

While the range string is the standard form of the autoFilter, the worksheet will also support the following values:

// Set an auto filter from A1 to C1
worksheet.autoFilter = {
  from: 'A1',
  to: 'C1',
}

// Set an auto filter from the cell in row 3 and column 1
// to the cell in row 5 and column 12
worksheet.autoFilter = {
  from: {
    row: 3,
    column: 1
  },
  to: {
    row: 5,
    column: 12
  }
}

// Set an auto filter from D3 to the
// cell in row 7 and column 5
worksheet.autoFilter = {
  from: 'D3',
  to: {
    row: 7,
    column: 5
  }
}

Columns

// Add column headers and define column keys and widths
// Note: these column structures are a workbook-building convenience only,
// apart from the column width, they will not be fully persisted.
worksheet.columns = [
  { header: 'Id', key: 'id', width: 10 },
  { header: 'Name', key: 'name', width: 32 },
  { header: 'D.O.B.', key: 'DOB', width: 10, outlineLevel: 1 }
];

// Access an individual columns by key, letter and 1-based column number
var idCol = worksheet.getColumn('id');
var nameCol = worksheet.getColumn('B');
var dobCol = worksheet.getColumn(3);

// set column properties

// Note: will overwrite cell value C1
dobCol.header = 'Date of Birth';

// Note: this will overwrite cell values C1:C2
dobCol.header = ['Date of Birth', 'A.K.A. D.O.B.'];

// from this point on, this column will be indexed by 'dob' and not 'DOB'
dobCol.key = 'dob';

dobCol.width = 15;

// Hide the column if you'd like
dobCol.hidden = true;

// set an outline level for columns
worksheet.getColumn(4).outlineLevel = 0;
worksheet.getColumn(5).outlineLevel = 1;

// columns support a readonly field to indicate the collapsed state based on outlineLevel
expect(worksheet.getColumn(4).collapsed).to.equal(false);
expect(worksheet.getColumn(5).collapsed).to.equal(true);

// iterate over all current cells in this column
dobCol.eachCell(function(cell, rowNumber) {
  // ...
});

// iterate over all current cells in this column including empty cells
dobCol.eachCell({ includeEmpty: true }, function(cell, rowNumber) {
  // ...
});

// add a column of new values
worksheet.getColumn(6).values = [1,2,3,4,5];

// add a sparse column of values
worksheet.getColumn(7).values = [,,2,3,,5,,7,,,,11];

// cut one or more columns (columns to the right are shifted left)
// If column properties have been defined, they will be cut or moved accordingly
// Known Issue: If a splice causes any merged cells to move, the results may be unpredictable
worksheet.spliceColumns(3,2);

// remove one column and insert two more.
// Note: columns 4 and above will be shifted right by 1 column.
// Also: If the worksheet has more rows than values in the column inserts,
//  the rows will still be shifted as if the values existed
var newCol3Values = [1,2,3,4,5];
var newCol4Values = ['one', 'two', 'three', 'four', 'five'];
worksheet.spliceColumns(3, 1, newCol3Values, newCol4Values);

Rows

// Add a couple of Rows by key-value, after the last current row, using the column keys
worksheet.addRow({id: 1, name: 'John Doe', dob: new Date(1970,1,1)});
worksheet.addRow({id: 2, name: 'Jane Doe', dob: new Date(1965,1,7)});

// Add a row by contiguous Array (assign to columns A, B & C)
worksheet.addRow([3, 'Sam', new Date()]);

// Add a row by sparse Array (assign to columns A, E & I)
var rowValues = [];
rowValues[1] = 4;
rowValues[5] = 'Kyle';
rowValues[9] = new Date();
worksheet.addRow(rowValues);

// Add an array of rows
var rows = [
  [5,'Bob',new Date()], // row by array
  {id:6, name: 'Barbara', dob: new Date()}
];
worksheet.addRows(rows);

// Get a row object. If it doesn't already exist, a new empty one will be returned
var row = worksheet.getRow(5);

// Get the last editable row in a worksheet (or undefined if there are none)
var row = worksheet.lastRow;

// Set a specific row height
row.height = 42.5;

// make row hidden
row.hidden = true;

// set an outline level for rows
worksheet.getRow(4).outlineLevel = 0;
worksheet.getRow(5).outlineLevel = 1;

// rows support a readonly field to indicate the collapsed state based on outlineLevel
expect(worksheet.getRow(4).collapsed).to.equal(false);
expect(worksheet.getRow(5).collapsed).to.equal(true);


row.getCell(1).value = 5; // A5's value set to 5
row.getCell('name').value = 'Zeb'; // B5's value set to 'Zeb' - assuming column 2 is still keyed by name
row.getCell('C').value = new Date(); // C5's value set to now

// Get a row as a sparse array
// Note: interface change: worksheet.getRow(4) ==> worksheet.getRow(4).values
row = worksheet.getRow(4).values;
expect(row[5]).toEqual('Kyle');

// assign row values by contiguous array (where array element 0 has a value)
row.values = [1,2,3];
expect(row.getCell(1).value).toEqual(1);
expect(row.getCell(2).value).toEqual(2);
expect(row.getCell(3).value).toEqual(3);

// assign row values by sparse array  (where array element 0 is undefined)
var values = []
values[5] = 7;
values[10] = 'Hello, World!';
row.values = values;
expect(row.getCell(1).value).toBeNull();
expect(row.getCell(5).value).toEqual(7);
expect(row.getCell(10).value).toEqual('Hello, World!');

// assign row values by object, using column keys
row.values = {
  id: 13,
  name: 'Thing 1',
  dob: new Date()
};

// Insert a page break below the row
row.addPageBreak();

// Iterate over all rows that have values in a worksheet
worksheet.eachRow(function(row, rowNumber) {
  console.log('Row ' + rowNumber + ' = ' + JSON.stringify(row.values));
});

// Iterate over all rows (including empty rows) in a worksheet
worksheet.eachRow({ includeEmpty: true }, function(row, rowNumber) {
  console.log('Row ' + rowNumber + ' = ' + JSON.stringify(row.values));
});

// Iterate over all non-null cells in a row
row.eachCell(function(cell, colNumber) {
  console.log('Cell ' + colNumber + ' = ' + cell.value);
});

// Iterate over all cells in a row (including empty cells)
row.eachCell({ includeEmpty: true }, function(cell, colNumber) {
  console.log('Cell ' + colNumber + ' = ' + cell.value);
});

// Cut one or more rows (rows below are shifted up)
// Known Issue: If a splice causes any merged cells to move, the results may be unpredictable
worksheet.spliceRows(4,3);

// remove one row and insert two more.
// Note: rows 4 and below will be shifted down by 1 row.
var newRow3Values = [1,2,3,4,5];
var newRow4Values = ['one', 'two', 'three', 'four', 'five'];
worksheet.spliceRows(3, 1, newRow3Values, newRow4Values);

// Cut one or more cells (cells to the right are shifted left)
// Note: this operation will not affect other rows
row.splice(3,2);

// remove one cell and insert two more (cells to the right of the cut cell will be shifted right)
row.splice(4,1,'new value 1', 'new value 2');

// Commit a completed row to stream
row.commit();

// row metrics
var rowSize = row.cellCount;
var numValues = row.actualCellCount;

Handling Individual Cells

var cell = worksheet.getCell('C3');

// Modify/Add individual cell
cell.value = new Date(1968, 5, 1);

// query a cell's type
expect(cell.type).toEqual(Excel.ValueType.Date);

// use string value of cell
myInput.value = cell.text;

// use html-safe string for rendering...
var html = '<div>' + cell.html + '</div>';

Merged Cells

// merge a range of cells
worksheet.mergeCells('A4:B5');

// ... merged cells are linked
worksheet.getCell('B5').value = 'Hello, World!';
expect(worksheet.getCell('B5').value).toBe(worksheet.getCell('A4').value);
expect(worksheet.getCell('B5').master).toBe(worksheet.getCell('A4'));

// ... merged cells share the same style object
expect(worksheet.getCell('B5').style).toBe(worksheet.getCell('A4').style);
worksheet.getCell('B5').style.font = myFonts.arial;
expect(worksheet.getCell('A4').style.font).toBe(myFonts.arial);

// unmerging the cells breaks the style links
worksheet.unMergeCells('A4');
expect(worksheet.getCell('B5').style).not.toBe(worksheet.getCell('A4').style);
expect(worksheet.getCell('B5').style.font).not.toBe(myFonts.arial);

// merge by top-left, bottom-right
worksheet.mergeCells('K10', 'M12');

// merge by start row, start column, end row, end column (equivalent to K10:M12)
worksheet.mergeCells(10,11,12,13);

Duplicate a Row

duplicateRow(start, amount = 1, insert = true)

const wb = new ExcelJS.Workbook();
const ws = wb.addWorksheet('duplicateTest');
ws.getCell('A1').value = 'One';
ws.getCell('A2').value = 'Two';
ws.getCell('A3').value = 'Three';
ws.getCell('A4').value = 'Four';

// This line will duplicate the row 'One' twice but it will replace rows 'Two' and 'Three'
// if third param was true so it would insert 2 new rows with the values and styles of row 'One'
ws.duplicateRow(1,2,false);

| Parameter | Description | Default Value | | -------------- | ----------------- | -------- | | start | Row number you want to duplicate (first in excel is 1) | | | amount | The times you want to duplicate the row | 1 | | insert | true if you want to insert new rows for the duplicates, or false if you want to replace them | true |

Defined Names

Individual cells (or multiple groups of cells) can have names assigned to them. The names can be used in formulas and data validation (and probably more).

// assign (or get) a name for a cell (will overwrite any other names that cell had)
worksheet.getCell('A1').name = 'PI';
expect(worksheet.getCell('A1').name).to.equal('PI');

// assign (or get) an array of names for a cell (cells can have more than one name)
worksheet.getCell('A1').names = ['thing1', 'thing2'];
expect(worksheet.getCell('A1').names).to.have.members(['thing1', 'thing2']);

// remove a name from a cell
worksheet.getCell('A1').removeName('thing1');
expect(worksheet.getCell('A1').names).to.have.members(['thing2']);

Data Validations

Cells can define what values are valid or not and provide prompting to the user to help guide them.

Validation types can be one of the following:

| Type | Description | | ---------- | ----------- | | list | Define a discrete set of valid values. Excel will offer these in a dropdown for easy entry | | whole | The value must be a whole number | | decimal | The value must be a decimal number | | textLength | The value may be text but the length is controlled | | custom | A custom formula controls the valid values |

For types other than list or custom, the following operators affect the validation:

| Operator | Description | | -------------------- | ----------- | | between | Values must lie between formula results | | notBetween | Values must not lie between formula results | | equal | Value must equal formula result | | notEqual | Value must not equal formula result | | greaterThan | Value must be greater than formula result | | lessThan | Value must be less than formula result | | greaterThanOrEqual | Value must be greater than or equal to formula result | | lessThanOrEqual | Value must be less than or equal to formula result |

// Specify list of valid values (One, Two, Three, Four).
// Excel will provide a dropdown with these values.
worksheet.getCell('A1').dataValidation = {
  type: 'list',
  allowBlank: true,
  formulae: ['"One,Two,Three,Four"']
};

// Specify list of valid values from a range.
// Excel will provide a dropdown with these values.
worksheet.getCell('A1').dataValidation = {
  type: 'list',
  allowBlank: true,
  formulae: ['$D$5:$F$5']
};

// Specify Cell must be a whole number that is not 5.
// Show the user an appropriate error message if they get it wrong
worksheet.getCell('A1').dataValidation = {
  type: 'whole',
  operator: 'notEqual',
  showErrorMessage: true,
  formulae: [5],
  errorStyle: 'error',
  errorTitle: 'Five',
  error: 'The value must not be Five'
};

// Specify Cell must be a decimal number between 1.5 and 7.
// Add 'tooltip' to help guid the user
worksheet.getCell('A1').dataValidation = {
  type: 'decimal',
  operator: 'between',
  allowBlank: true,
  showInputMessage: true,
  formulae: [1.5, 7],
  promptTitle: 'Decimal',
  prompt: 'The value must between 1.5 and 7'
};

// Specify Cell must have a text length less than 15
worksheet.getCell('A1').dataValidation = {
  type: 'textLength',
  operator: 'lessThan',
  showErrorMessage: true,
  allowBlank: true,
  formulae: [15]
};

// Specify Cell must be a date before 1st Jan 2016
worksheet.getCell('A1').dataValidation = {
  type: 'date',
  operator: 'lessThan',
  showErrorMessage: true,
  allowBlank: true,
  formulae: [new Date(2016,0,1)]
};

Cell Comments

Add old style comment to a cell

// plain text note
worksheet.getCell('A1').note = 'Hello, ExcelJS!';

// colourful formatted note
ws.getCell('B1').note = {
  texts: [
    {'font': {'size': 12, 'color': {'theme': 0}, 'name': 'Calibri', 'family': 2, 'scheme': 'minor'}, 'text': 'This is '},
    {'font': {'italic': true, 'size': 12, 'color': {'theme': 0}, 'name': 'Calibri', 'scheme': 'minor'}, 'text': 'a'},
    {'font': {'size': 12, 'color': {'theme': 1}, 'name': 'Calibri', 'family': 2, 'scheme': 'minor'}, 'text': ' '},
    {'font': {'size': 12, 'color': {'argb': 'FFFF6600'}, 'name': 'Calibri', 'scheme': 'minor'}, 'text': 'colorful'},
    {'font': {'size': 12, 'color': {'theme': 1}, 'name': 'Calibri', 'family': 2, 'scheme': 'minor'}, 'text': ' text '},
    {'font': {'size': 12, 'color': {'argb': 'FFCCFFCC'}, 'name': 'Calibri', 'scheme': 'minor'}, 'text': 'with'},
    {'font': {'size': 12, 'color': {'theme': 1}, 'name': 'Calibri', 'family': 2, 'scheme': 'minor'}, 'text': ' in-cell '},
    {'font': {'bold': true, 'size': 12, 'color': {'theme': 1}, 'name': 'Calibri', 'family': 2, 'scheme': 'minor'}, 'text': 'format'},
  ],
};

Tables

Tables allow for in-sheet manipulation of tabular data.

To add a table to a worksheet, define a table model and call addTable:

// add a table to a sheet
ws.addTable({
  name: 'MyTable',
  ref: 'A1',
  headerRow: true,
  totalsRow: true,
  style: {
    theme: 'TableStyleDark3',
    showRowStripes: true,
  },
  columns: [
    {name: 'Date', totalsRowLabel: 'Totals:', filterButton: true},
    {name: 'Amount', totalsRowFunction: 'sum', filterButton: false},
  ],
  rows: [
    [new Date('2019-07-20'), 70.10],
    [new Date('2019-07-21'), 70.60],
    [new Date('2019-07-22'), 70.10],
  ],
});

Note: Adding a table to a worksheet will modify the sheet by placing headers and row data to the sheet. Any data on the sheet covered by the resulting table (including headers and totals) will be overwritten.

Table Properties

The following table defines the properties supported by tables.

| Table Property | Description | Required | Default Value | | -------------- | ----------------- | -------- | ------------- | | name | The name of the table | Y | | | displayName | The display name of the table | N | name | | ref | Top left cell of the table | Y | | | headerRow | Show headers at top of table | N | true | | totalsRow | Show totals at bottom of table | N | false | | style | Extra style properties | N | {} | | columns | Column definitions | Y | | | rows | Rows of data | Y | |

Table Style Properties

The following table defines the properties supported within the table style property.

| Style Property | Description | Required | Default Value | | ------------------ | ----------------- | -------- | ------------- | | theme | The colour theme of the table | N | 'TableStyleMedium2' | | showFirstColumn | Highlight the first column (bold) | N | false | | showLastColumn | Highlight the last column (bold) | N | false | | showRowStripes | Alternate rows shown with background colour | N | false | | showColumnStripes | Alternate rows shown with background colour | N | false |

Table Column Properties

The following table defines the properties supported within each table column.

| Column Property | Description | Required | Default Value | | ------------------ | ----------------- | -------- | ------------- | | name | The name of the column, also used in the header | Y | | | filterButton | Switches the filter control in the header | N | false | | totalsRowLabel | Label to describe the totals row (first column) | N | 'Total' | | totalsRowFunction | Name of the totals function | N | 'none' | | totalsRowFormula | Optional formula for custom functions | N | |

Totals Functions

The following table list the valid values for the totalsRowFunction property defined by columns. If any value other than 'custom' is used, it is not necessary to include the associated formula as this will be inserted by the table.

| Totals Functions | Description | | ------------------ | ----------------- | | none | No totals function for this column | | average | Compute average for the column | | countNums | Count the entries that are numbers | | count | Count of entries | | max | The maximum value in this column | | min | The minimum value in this column | | stdDev | The standard deviation for this column | | var | The variance for this column | | sum | The sum of entries for this column | | custom | A custom formula. Requires an associated totalsRowFormula value. |

Table Style Themes

Valid theme names follow the following pattern:

• "TableStyle[Shade][Number]"

Shades, Numbers can be one of:

• Light, 1-21
• Medium, 1-28
• Dark, 1-11

For no theme, use the value null.

Note: custom table themes are not supported by exceljs yet.

Modifying Tables

Tables support a set of manipulation functions that allow data to be added or removed and some properties to be changed. Since many of these operations may have on-sheet effects, the changes must be committed once complete.

All index values in the table are zero based, so the first row number and first column number is 0.

Adding or Removing Headers and Totals

const table = ws.getTable('MyTable');

// turn header row on
table.headerRow = true;

// turn totals row off
table.totalsRow = false;

// commit the table changes into the sheet
table.commit();

Relocating a Table

const table = ws.getTable('MyTable');

// table top-left move to D4
table.ref = 'D4';

// commit the table changes into the sheet
table.commit();

Adding and Removing Rows

const table = ws.getTable('MyTable');

// remove first two rows
table.removeRows(0, 2);

// insert new rows at index 5
table.addRow([new Date('2019-08-05'), 5, 'Mid'], 5);

// append new row to bottom of table
table.addRow([new Date('2019-08-10'), 10, 'End']);

// commit the table changes into the sheet
table.commit();

Adding and Removing Columns

const table = ws.getTable('MyTable');

// remove second column
table.removeColumns(1, 1);

// insert new column (with data) at index 1
table.addColumn(
  {name: 'Letter', totalsRowFunction: 'custom', totalsRowFormula: 'ROW()', totalsRowResult: 6, filterButton: true},
  ['a', 'b', 'c', 'd'],
  2
);

// commit the table changes into the sheet
table.commit();

Change Column Properties

const table = ws.getTable('MyTable');

// Get Column Wrapper for second column
const column = table.getColumn(1);

// set some properties
column.name = 'Code';
column.filterButton = true;
column.style = {font:{bold: true, name: 'Comic Sans MS'}};
column.totalsRowLabel = 'Totals';
column.totalsRowFunction = 'custom';
column.totalsRowFormula = 'ROW()';
column.totalsRowResult = 10;

// commit the table changes into the sheet
table.commit();

Styles

Cells, Rows and Columns each support a rich set of styles and formats that affect how the cells are displayed.

Styles are set by assigning the following properties:

• numFmt
• font
• alignment
• border
• fill

// assign a style to a cell
ws.getCell('A1').numFmt = '0.00%';

// Apply styles to worksheet columns
ws.columns = [
  { header: 'Id', key: 'id', width: 10 },
  { header: 'Name', key: 'name', width: 32, style: { font: { name: 'Arial Black' } } },
  { header: 'D.O.B.', key: 'DOB', width: 10, style: { numFmt: 'dd/mm/yyyy' } }
];

// Set Column 3 to Currency Format
ws.getColumn(3).numFmt = '"£"#,##0.00;[Red]\-"£"#,##0.00';

// Set Row 2 to Comic Sans.
ws.getRow(2).font = { name: 'Comic Sans MS', family: 4, size: 16, underline: 'double', bold: true };

When a style is applied to a row or column, it will be applied to all currently existing cells in that row or column. Also, any new cell that is created will inherit its initial styles from the row and column it belongs to.

If a cell's row and column both define a specific style (e.g. font), the cell will use the row style over the column style. However if the row and column define different styles (e.g. column.numFmt and row.font), the cell will inherit the font from the row and the numFmt from the column.

Caveat: All the above properties (with the exception of numFmt, which is a string), are JS object structures. If the same style object is assigned to more than one spreadsheet entity, then each entity will share the same style object. If the style object is later modified before the spreadsheet is serialized, then all entities referencing that style object will be modified too. This behaviour is intended to prioritize performance by reducing the number of JS objects created. If you want the style objects to be independent, you will need to clone them before assigning them. Also, by default, when a document is read from file (or stream) if spreadsheet entities share similar styles, then they will reference the same style object too.

Number Formats

// display value as '1 3/5'
ws.getCell('A1').value = 1.6;
ws.getCell('A1').numFmt = '# ?/?';

// display value as '1.60%'
ws.getCell('B1').value = 0.016;
ws.getCell('B1').numFmt = '0.00%';

Fonts

// for the wannabe graphic designers out there
ws.getCell('A1').font = {
  name: 'Comic Sans MS',
  family: 4,
  size: 16,
  underline: true,
  bold: true
};

// for the graduate graphic designers...
ws.getCell('A2').font = {
  name: 'Arial Black',
  color: { argb: 'FF00FF00' },
  family: 2,
  size: 14,
  italic: true
};

// for the vertical align
ws.getCell('A3').font = {
  vertAlign: 'superscript'
};

// note: the cell will store a reference to the font object assigned.
// If the font object is changed afterwards, the cell font will change also...
var font = { name: 'Arial', size: 12 };
ws.getCell('A3').font = font;
font.size = 20; // Cell A3 now has font size 20!

// Cells that share similar fonts may reference the same font object after
// the workbook is read from file or stream

| Font Property | Description | Example Value(s) | | ------------- | ----------------- | ---------------- | | name | Font name. | 'Arial', 'Calibri', etc. | | family | Font family for fallback. An integer value. | 1 - Serif, 2 - Sans Serif, 3 - Mono, Others - unknown | | scheme | Font scheme. | 'minor', 'major', 'none' | | charset | Font charset. An integer value. | 1, 2, etc. | | size | Font size. An integer value. | 9, 10, 12, 16, etc. | | color | Colour description, an object containing an ARGB value. | { argb: 'FFFF0000'} | | bold | Font weight | true, false | | italic | Font slope | true, false | | underline | Font underline style | true, false, 'none', 'single', 'double', 'singleAccounting', 'doubleAccounting' | | strike | Font strikethrough | true, false | | outline | Font outline | true, false | | vertAlign | Vertical align | 'superscript', 'subscript'

Alignment

// set cell alignment to top-left, middle-center, bottom-right
ws.getCell('A1').alignment = { vertical: 'top', horizontal: 'left' };
ws.getCell('B1').alignment = { vertical: 'middle', horizontal: 'center' };
ws.getCell('C1').alignment = { vertical: 'bottom', horizontal: 'right' };

// set cell to wrap-text
ws.getCell('D1').alignment = { wrapText: true };

// set cell indent to 1
ws.getCell('E1').alignment = { indent: 1 };

// set cell text rotation to 30deg upwards, 45deg downwards and vertical text
ws.getCell('F1').alignment = { textRotation: 30 };
ws.getCell('G1').alignment = { textRotation: -45 };
ws.getCell('H1').alignment = { textRotation: 'vertical' };

Valid Alignment Property Values

| horizontal | vertical | wrapText | shrinkToFit | indent | readingOrder | textRotation | | ---------------- | ----------- | -------- | ----------- | ------- | ------------ | ------------ | | left | top | true | true | integer | rtl | 0 to 90 | | center | middle | false | false | | ltr | -1 to -90 | | right | bottom | | | | | vertical | | fill | distributed | | | | | | | justify | justify | | | | | | | centerContinuous | | | | | | | | distributed | | | | | | |

Borders

// set single thin border around A1
ws.getCell('A1').border = {
  top: {style:'thin'},
  left: {style:'thin'},
  bottom: {style:'thin'},
  right: {style:'thin'}
};

// set double thin green border around A3
ws.getCell('A3').border = {
  top: {style:'double', color: {argb:'FF00FF00'}},
  left: {style:'double', color: {argb:'FF00FF00'}},
  bottom: {style:'double', color: {argb:'FF00FF00'}},
  right: {style:'double', color: {argb:'FF00FF00'}}
};

// set thick red cross in A5
ws.getCell('A5').border = {
  diagonal: {up: true, down: true, style:'thick', color: {argb:'FFFF0000'}}
};

Valid Border Styles

• thin
• dotted
• dashDot
• hair
• dashDotDot
• slantDashDot
• mediumDashed
• mediumDashDotDot
• mediumDashDot
• medium
• double
• thick

Fills

// fill A1 with red darkVertical stripes
ws.getCell('A1').fill = {
  type: 'pattern',
  pattern:'darkVertical',
  fgColor:{argb:'FFFF0000'}
};

// fill A2 with yellow dark trellis and blue behind
ws.getCell('A2').fill = {
  type: 'pattern',
  pattern:'darkTrellis',
  fgColor:{argb:'FFFFFF00'},
  bgColor:{argb:'FF0000FF'}
};

// fill A3 with blue-white-blue gradient from left to right
ws.getCell('A3').fill = {
  type: 'gradient',
  gradient: 'angle',
  degree: 0,
  stops: [
    {position:0, color:{argb:'FF0000FF'}},
    {position:0.5, color:{argb:'FFFFFFFF'}},
    {position:1, color:{argb:'FF0000FF'}}
  ]
};


// fill A4 with red-green gradient from center
ws.getCell('A4').fill = {
  type: 'gradient',
  gradient: 'path',
  center:{left:0.5,top:0.5},
  stops: [
    {position:0, color:{argb:'FFFF0000'}},
    {position:1, color:{argb:'FF00FF00'}}
  ]
};

Pattern Fills

| Property | Required | Description | | -------- | -------- | ----------- | | type | Y | Value: 'pattern'Specifies this fill uses patterns | | pattern | Y | Specifies type of pattern (see Valid Pattern Types below) | | fgColor | N | Specifies the pattern foreground color. Default is black. | | bgColor | N | Specifies the pattern background color. Default is white. |

Valid Pattern Types

• none
• solid
• darkGray
• mediumGray
• lightGray
• gray125
• gray0625
• darkHorizontal
• darkVertical
• darkDown
• darkUp
• darkGrid
• darkTrellis
• lightHorizontal
• lightVertical
• lightDown
• lightUp
• lightGrid
• lightTrellis

Gradient Fills

| Property | Required | Description | | -------- | -------- | ----------- | | type | Y | Value: 'gradient'Specifies this fill uses gradients | | gradient | Y | Specifies gradient type. One of ['angle', 'path'] | | degree | angle | For 'angle' gradient, specifies the direction of the gradient. 0 is from the left to the right. Values from 1 - 359 rotates the direction clockwise | | center | path | For 'path' gradient. Specifies the relative coordinates for the start of the path. 'left' and 'top' values range from 0 to 1 | | stops | Y | Specifies the gradient colour sequence. Is an array of objects containing position and color starting with position 0 and ending with position 1. Intermediary positions may be used to specify other colours on the path. |

Caveats

Using the interface above it may be possible to create gradient fill effects not possible using the XLSX editor program. For example, Excel only supports angle gradients of 0, 45, 90 and 135. Similarly the sequence of stops may also be limited by the UI with positions [0,1] or [0,0.5,1] as the only options. Take care with this fill to be sure it is supported by the target XLSX viewers.

Rich Text

Individual cells now support rich text or in-cell formatting. Rich text values can control the font properties of any number of sub-strings within the text value. See Fonts for a complete list of details on what font properties are supported.

ws.getCell('A1').value = {
  'richText': [
    {'font': {'size': 12,'color': {'theme': 0},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': 'This is '},
    {'font': {'italic': true,'size': 12,'color': {'theme': 0},'name': 'Calibri','scheme': 'minor'},'text': 'a'},
    {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' '},
    {'font': {'size': 12,'color': {'argb': 'FFFF6600'},'name': 'Calibri','scheme': 'minor'},'text': 'colorful'},
    {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' text '},
    {'font': {'size': 12,'color': {'argb': 'FFCCFFCC'},'name': 'Calibri','scheme': 'minor'},'text': 'with'},
    {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' in-cell '},
    {'font': {'bold': true,'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': 'format'}
  ]
};

expect(ws.getCell('A1').text).to.equal('This is a colorful text with in-cell format');
expect(ws.getCell('A1').type).to.equal(Excel.ValueType.RichText);

Cell Protection

Cell level protection can be modified using the protection property.

ws.getCell('A1').protection = {
  locked: false,
  hidden: true,
};

Supported Protection Properties

| Property | Default | Description | | -------- | ------- | ----------- | | locked | true | Specifies whether a cell will be locked if the sheet is protected. | | hidden | false | Specifies whether a cell's formula will be visible if the sheet is protected. |

Conditional Formatting

Conditional formatting allows a sheet to show specific styles, icons, etc depending on cell values or any arbitrary formula.

Conditional formatting rules are added at the sheet level and will typically cover a range of cells.

Multiple rules can be applied to a given cell range and each rule will apply its own style.

If multiple rules affect a given cell, the rule priority value will determine which rule wins out if competing styles collide. The rule with the lower priority value wins. If priority values are not specified for a given rule, ExcelJS will assign them in ascending order.

Note: at present, only a subset of conditional formatting rules are supported. Specifically, only the formatting rules that do not require XML rendering inside an <extLst> element. This means that datasets and three specific icon sets (3Triangles, 3Stars, 5Boxes) are not supported.

// add a checkerboard pattern to A1:E7 based on row + col being even or odd
worksheet.addConditionalFormatting({
  ref: 'A1:E7',
  rules: [
    {
      type: 'expression',
      formulae: ['MOD(ROW()+COLUMN(),2)=0'],
      style: {fill: {type: 'pattern', pattern: 'solid', bgColor: {argb: 'FF00FF00'}}},
    }
  ]
})

Supported Conditional Formatting Rule Types

| Type | Description | | ------------ | ----------- | | expression | Any custom function may be used to activate the rule. | | cellIs | Compares cell value with supplied formula using specified operator | | top10 | Applies formatting to cells with values in top (or bottom) ranges | | aboveAverage | Applies formatting to cells with values above (or below) average | | colorScale | Applies a coloured background to cells based on where their values lie in the range | | iconSet | Adds one of a range of icons to cells based on value | | containsText | Applies formatting based on whether cell a specific text | | timePeriod | Applies formatting based on whether cell datetime value lies within a specified range |

Expression

| Field | Optional | Default | Description | | -------- | -------- | ------- | ----------- | | type | | | 'expression' | | priority | Y | <auto> | determines priority ordering of styles | | formulae | | | array of 1 formula string that returns a true/false value. To reference the cell value, use the top-left cell address | | style | | | style structure to apply if the formula returns true |

Cell Is

| Field | Optional | Default | Description | | -------- | -------- | ------- | ----------- | | type | | | 'cellIs' | | priority | Y | <auto> | determines priority ordering of styles | | operator | | | how to compare cell value with formula result | | formulae | | | array of 1 formula string that returns the value to compare against each cell | | style | | | style structure to apply if the comparison returns true |

Cell Is Operators

| Operator | Description | | ----------- | ----------- | | equal | Apply format if cell value equals formula value | | greaterThan | Apply format if cell value is greater than formula value | | lessThan | Apply format if cell value is less than formula value | | between | Apply format if cell value is between two formula values (inclusive) |

Top 10

| Field | Optional | Default | Description | | -------- | -------- | ------- | ----------- | | type | | | 'top10' | | priority | Y | <auto> | determines priority ordering of styles | | rank | Y | 10 | specifies how many top (or bottom) values are included in the formatting | | percent | Y | false | if true, the rank field is a percentage, not an absolute | | bottom | Y | false | if true, the bottom values are included instead of the top | | style | | | style structure to apply if the comparison returns true |

Above Average

| Field | Optional | Default | Description | | ------------- | -------- | ------- | ----------- | | type | | | 'aboveAverage' | | priority | Y | <auto> | determines priority ordering of styles | | aboveAverage | Y | false | if true, the rank field is a percentage, not an absolute | | style | | | style structure to apply if the comparison returns true |

Colour Scale

| Field | Optional | Default | Description | | ------------- | -------- | ------- | ----------- | | type | | | 'colorScale' | | priority | Y | <auto> | determines priority ordering of styles | | cfvo | | | array of 2 to 5 Conditional Formatting Value Objects specifying way-points in the value range | | color | | | corresponding array of colours to use at given way points | | style | | | style structure to apply if the comparison returns true |

Icon Set

| Field | Optional | Default | Description | | ------------- | -------- | ------- | ----------- | | type | | | 'iconSet' | | priority | Y | <auto> | determines priority ordering of styles | | iconSet | Y | 3TrafficLights | name of icon set to use | | cfvo | | | array of 2 to 5 Conditional Formatting Value Objects specifying way-points in the value range | | style | | | style structure to apply if the comparison returns true |

Contains Text

| Field | Optional | Default | Description | | -------- | -------- | ------- | ----------- | | type | | | 'containsText' | | priority | Y | <auto> | determines priority ordering of styles | | operator | | | type of text comparison | | text | | | text to search for | | style | | | style structure to apply if the comparison returns true |

Contains Text Operators

| Operator | Description | | ----------------- | ----------- | | containsText | Apply format if cell value contains the value specified in the 'text' field | | containsBlanks | Apply format if cell value contains blanks | | notContainsBlanks | Apply format if cell value does not contain blanks | | containsErrors | Apply format if cell value contains errors | | notContainsErrors | Apply format if cell value does not contain errors |

Time Period

| Field | Optional | Default | Description | | ---------- | -------- | ------- | ----------- | | type | | | 'timePeriod' | | priority | Y | <auto> | determines priority ordering of styles | | timePeriod | | | what time period to compare cell value to | | style | | | style structure to apply if the comparison returns true |

Time Periods

| Time Period | Description | | ----------------- | ----------- | | lastWeek | Apply format if cell value falls within the last week | | thisWeek | Apply format if cell value falls in this week | | nextWeek | Apply format if cell value falls in the next week | | yesterday | Apply format if cell value is equal to yesterday | | today | Apply format if cell value is equal to today | | tomorrow | Apply format if cell value is equal to tomorrow | | last7Days | Apply format if cell value falls within the last 7 days | | lastMonth | Apply format if cell value falls in last month | | thisMonth | Apply format if cell value falls in this month | | nextMonth | Apply format if cell value falls in next month |

Outline Levels

Excel supports outlining; where rows or columns can be expanded or collapsed depending on what level of detail the user wishes to view.

Outline levels can be defined in column setup:

worksheet.columns = [
  { header: 'Id', key: 'id', width: 10 },
  { header: 'Name', key: 'name', width: 32 },
  { header: 'D.O.B.', key: 'DOB', width: 10, outlineLevel: 1 }
];

Or directly on the row or column

worksheet.getColumn(3).outlineLevel = 1;
worksheet.getRow(3).outlineLevel = 1;

The sheet outline levels can be set on the worksheet

// set column outline level
worksheet.properties.outlineLevelCol = 1;

// set row outline level
worksheet.properties.outlineLevelRow = 1;

Note: adjusting outline levels on rows or columns or the outline levels on the worksheet will incur a side effect of also modifying the collapsed property of all rows or columns affected by the property change. E.g.:

worksheet.properties.outlineLevelCol = 1;

worksheet.getColumn(3).outlineLevel = 1;
expect(worksheet.getColumn(3).collapsed).to.be.true;

worksheet.properties.outlineLevelCol = 2;
expect(worksheet.getColumn(3).collapsed).to.be.false;

The outline properties can be set on the worksheet

worksheet.properties.outlineProperties = {
  summaryBelow: false,
  summaryRight: false,
};

Images

Adding images to a worksheet is a two-step process. First, the image is added to the workbook via the addImage() function which will also return an imageId value. Then, using the imageId, the image can be added to the worksheet either as a tiled background or covering a cell range.

Note: As of this version, adjusting or transforming the image is not supported.

Add Image to Workbook

The Workbook.addImage function supports adding images by filename or by Buffer. Note that in both cases, the extension must be specified. Valid extension values include 'jpeg', 'png', 'gif'.

// add image to workbook by filename
var imageId1 = workbook.addImage({
  filename: 'path/to/image.jpg',
  extension: 'jpeg',
});

// add image to workbook by buffer
var imageId2 = workbook.addImage({
  buffer: fs.readFileSync('path/to.image.png'),
  extension: 'png',
});

// add image to workbook by base64
var myBase64Image = "data:image/png;base64,iVBORw0KG...";
var imageId2 = workbook.addImage({
  base64: myBase64Image,
  extension: 'png',
});

Add image background to worksheet

Using the image id from Workbook.addImage, the background to a worksheet can be set using the addBackgroundImage function

// set background
worksheet.addBackgroundImage(imageId1);

Add image over a range

Using the image id from Workbook.addImage, an image can be embedded within the worksheet to cover a range. The coordinates calculated from the range will cover from the top-left of the first cell to the bottom right of the second.

// insert an image over B2:D6
worksheet.addImage(imageId2, 'B2:D6');

Using a structure instead of a range string, it is possible to partially cover cells.

Note that the coordinate system used for this is zero