is-css-hex-color

Function to determine if a string is a CSS hex color code

Description

Checks if a string is a valid CSS hex color code.

Valid CSS hex colors must:

• begin with a # character
• contain 3 hex numbers from 0 to ff
• may also contain a 4th hex number representing an alpha channel
• be in long (#123456) or short (#123) form

The following are examples of valid CSS hex colour codes:

#6699ee   // nearly cornflowerblue
#6699ee88 // ... with 53% transparency
#69e8     // ... in shorthand

See...

• Install/Usage
• Syntax
• Examples
• See Also

Install

npm install --save @chriscodesthings/is-css-hex-color

Use

import isCSSHexColor from '@chriscodesthings/is-css-hex-color';

console.log(isCSSHexColor("#123abcff"));
// => true

Syntax

isCSSHexColor(str);

Parameters

• str: text string to test

Return Value

Returns boolean true if str is a valid CSS hex color code, false otherwise.

Examples

// validate after user input
function setColour(col) {
    if( !isCSSHexColor(col)) {
        alert("Please input a valid CSS hex colour");
        return;
    }

    // set some colours
}

See Also...

• is-hex-number: Determine if a string is a hexadecimal number
• random-css-hex-color: Generates a random color in CSS hex format
• rgba-color-to-css-hex: Converts an RGB or RGBA color to a CSS hex color code
• color-object: Simple, lightweight class to store and manipulate a color, and convert between formats