enumjs

A Enum class library in javascript.

quick start

define with string or string array

var OS = new Enum('LINUX,WINDOWS');              // LINUX: 0, WINDOWS: 1
var MOBILE = new Enum(['ANDROID', 'IOS']);       // ANDROID: 0, IOS: 1

OS.LINUX.equals(0);           // true
+MOBILE.IOS === 1;            // true

The simplest way to create an Enum is using a string, in which you can change the seperators , with ; or \s. Or you can use an array to store your keys, which is recommanded.

define with object array

var PETS = new Enum([
    { key: 'DOG', name: 'DingDong', value: 100 },
    { key: 'CAT', name: 'Lily', value: 200 },
    { key: 'LIZARD', name: 'Keith', value: 300 },
]);     // DOG: 100, CAT: 200, LIZARD: 300

PETS.DOG.getName();               // DingDong
PETS.find(300).getName();        // Keith

In some cases, you might connect your enum keys to some other info, so you can just create your enum with an Object array, storing your relative infomation with your enum keys.

You can name the custom property whatever you want, but you can only access the propery via the get method, just like the javabean style, instead you cannot modify the property after defination.

usage

compare

The value of the Enum class is not a Number type, it cannot be compare to a number with === directly. Instead, method equals or eq is recommanded, or you can convert it to Number type explicitly.

var ENUMS = new ('A,B');

ENUMS.A == 0;           // true, not recommanded
ENUMS.A === 0;          // false
+ENUMS.A === 0;         // true
ENUMS.getValue() === 0; // true
ENUMS.v() === 0;        // true
ENUMS.A.equals(0);      // true
ENUMS.A.eq(0);          // true

get

The enum item can be accessed by it's value. An Enum item can

var GREETING = new ([
    { key: 'ENGLISH', greeting: 'Hello', value: 100 },
    { key: 'DEUTSCH', greeting: 'Guten tag', value: 200 },
    { key: 'CHINESE', greeting: '你好', value: 300 },
]);

GREETING.find(300);                         // GREETING.CHINESE
GREETING.find(300).getGreeting();           // 你好
GREETING.CHINESE.getGreeting();                // 你好
GREETING.find(function(item){
    return item.k() === 'CHINESE';
    // return item.k() === 'CHINESE';
}).getGreeting();                               // 你好

forEach

GREETING.forEach(function(item, key){
    console.log(key, item.v());
    // ENGLISH 100
    // DEUTSCH 200
    // CHINESE 300
});

map

var arr = GREETING.map(function(item, key){
    return key;
});
// [ 'ENGLISH', 'DEUTSCH', 'CHINESE' ]

filter

var TYPE = new Enum('A,B,C');
var arr = TYPE.filter(function(item, key){
    return item.v() > 0;
});
// [TYPE.B, TYPE.C]

keys

var TYPE = new Enum('A,B,C');
var keys = TYPE.keys();
// ['A', 'B', 'C']

values

var TYPE = new Enum('A,B,C');
var keys = TYPE.values();
// [0, 1, 2]

pick

var FRUIT = new Enum([
  {
    key: 'GRAPE',
    name: 'grape',
    color: 'purple'
  }
]);

var grape = FRUIT.GRAPE.pick(['name', 'color'])
// { name: 'grape', color: 'purple' }

pickAs

var FRUIT = new Enum([
  {
    key: 'GRAPE',
    name: 'grape',
    color: 'purple'
  }
]);

var grape = FRUIT.GRAPE.pickAs({
  name: 'fruit',
  color: 'colour'
});
// { fruit: 'grape', colour: 'purple' }