Create an enum with string values

TypeScript 2.4

Now has string enums so your code just works:

enum E {
    hello = "hello",
    world = "world"
};

🌹

TypeScript 1.8

Since TypeScript 1.8 you can use string literal types to provide a reliable and safe experience for named string values (which is partially what enums are used for).

type Options = "hello" | "world";
var foo: Options;
foo = "hello"; // Okay 
foo = "asdf"; // Error!

More : https://www.typescriptlang.org/docs/handbook/advanced-types.html#string-literal-types

Legacy Support

Enums in TypeScript are number based.

You can use a class with static members though:

class E
{
    static hello = "hello";
    static world = "world"; 
}

You could go plain as well:

var E = {
    hello: "hello",
    world: "world"
}

Update: Based on the requirement to be able to do something like var test:E = E.hello; the following satisfies this:

class E
{
    // boilerplate 
    constructor(public value:string){    
    }

    toString(){
        return this.value;
    }

    // values 
    static hello = new E("hello");
    static world = new E("world");
}

// Sample usage: 
var first:E = E.hello;
var second:E = E.world;
var third:E = E.hello;

console.log("First value is: "+ first);
console.log(first===third); 

In latest version (1.0RC) of TypeScript, you can use enums like this:

enum States {
    New,
    Active,
    Disabled
} 

// this will show message '0' which is number representation of enum member
alert(States.Active); 

// this will show message 'Disabled' as string representation of enum member
alert(States[States.Disabled]);

Update 1

To get number value of enum member from string value, you can use this:

var str = "Active";
// this will show message '1'
alert(States[str]);

Update 2

In latest TypeScript 2.4, there was introduced string enums, like this:

enum ActionType {
    AddUser = "ADD_USER",
    DeleteUser = "DELETE_USER",
    RenameUser = "RENAME_USER",

    // Aliases
    RemoveUser = DeleteUser,
}

For more info about TypeScript 2.4, read blog on MSDN.

TypeScript 2.4+

You can now assign string values directly to enum members:

enum Season {
    Winter = "winter",
    Spring = "spring",
    Summer = "summer",
    Fall = "fall"
}

See #15486 for more information.

TypeScript 1.8+

In TypeScript 1.8+, you can create a string literal type to define the type and an object with the same name for the list of values. It mimics a string enum's expected behaviour.

Here's an example:

type MyStringEnum = "member1" | "member2";

const MyStringEnum = {
    Member1: "member1" as MyStringEnum,
    Member2: "member2" as MyStringEnum
};

Which will work like a string enum:

// implicit typing example
let myVariable = MyStringEnum.Member1; // ok
myVariable = "member2";                // ok
myVariable = "some other value";       // error, desired

// explict typing example
let myExplicitlyTypedVariable: MyStringEnum;
myExplicitlyTypedVariable = MyStringEnum.Member1; // ok
myExplicitlyTypedVariable = "member2";            // ok
myExplicitlyTypedVariable = "some other value";   // error, desired

Make sure to type all the strings in the object! If you don't then in the first example above the variable would not be implicitly typed to MyStringEnum.

In TypeScript 0.9.0.1, although it occurs a compiler error, the compiler can still compile the ts file into js file. The code works as we expected and Visual Studio 2012 can support for automatic code completion.

Update :

In syntax, TypeScript doesn't allow us to create an enum with string values, but we can hack the compiler :p

enum Link
{
    LEARN   =   <any>'/Tutorial',
    PLAY    =   <any>'/Playground',
    GET_IT  =   <any>'/#Download',
    RUN_IT  =   <any>'/Samples',
    JOIN_IN =   <any>'/#Community'
}

alert('Link.LEARN:    '                     + Link.LEARN);
alert('Link.PLAY:    '                      + Link.PLAY);
alert('Link.GET_IT:    '                    + Link.GET_IT);
alert('Link[\'/Samples\']:    Link.'        + Link['/Samples']);
alert('Link[\'/#Community\']    Link.'      + Link['/#Community']);

Playground

TypeScript 2.1 +

Lookup types, introduced in TypeScript 2.1 allow another pattern for simulating string enums:

// String enums in TypeScript 2.1
const EntityType = {
    Foo: 'Foo' as 'Foo',
    Bar: 'Bar' as 'Bar'
};

function doIt(entity: keyof typeof EntityType) {
    // ...
}

EntityType.Foo          // 'Foo'
doIt(EntityType.Foo);   // 👍
doIt(EntityType.Bar);   // 👍
doIt('Foo');            // 👍
doIt('Bar');            // 👍
doIt('Baz');            // 🙁 

TypeScript 2.4 +

With version 2.4, TypeScript introduced native support for string enums, so the solution above is not needed. From the TS docs:

enum Colors {
  Red = "RED",
  Green = "GREEN",
  Blue = "BLUE",
}