以下代码可用于在TypeScript中创建enum:

enum e {
    hello = 1,
    world = 2
};

这些值可以通过以下方式访问:

e.hello;
e.world;

我如何创建一个字符串值enum ?

enum e {
    hello = "hello", // error: cannot convert string to e
    world = "world"  // error 
};

当前回答

TypeScript 2 + 4。

你现在可以直接将字符串值分配给enum成员:

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

更多信息见#15486。

打印稿1.8 +

在TypeScript 1.8+中,你可以创建一个字符串文字类型来定义类型,并为值列表创建一个同名的对象。它模仿字符串enum的预期行为。

这里有一个例子:

type MyStringEnum = "member1" | "member2";

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

它将像字符串enum一样工作:

// 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

确保输入对象中的所有字符串!如果不这样做,那么在上面的第一个例子中,变量将不会隐式地类型化为MyStringEnum。

其他回答

我正在寻找一种方法来实现typescript枚举中的描述(v2.5),这种模式适合我:

export enum PriceTypes {
    Undefined = 0,
    UndefinedDescription = 'Undefined' as any,
    UserEntered = 1,
    UserEnteredDescription = 'User Entered' as any,
    GeneratedFromTrade = 2,
    GeneratedFromTradeDescription = 'Generated From Trade' as any,
    GeneratedFromFreeze = 3,
    GeneratedFromFreezeDescription = 'Generated Rom Freeze' as any
}

...

    GetDescription(e: any, id: number): string {
        return e[e[id].toString() + "Description"];
    }
    getPriceTypeDescription(price: IPricePoint): string {
        return this.GetDescription(PriceTypes, price.priceType);
    }

这里有一个相当干净的解决方案,它允许继承,使用TypeScript 2.0。我没有在早期的版本上尝试过。

附加条件:该值可以是任何类型!

export class Enum<T> {
  public constructor(public readonly value: T) {}
  public toString() {
    return this.value.toString();
  }
}

export class PrimaryColor extends Enum<string> {
  public static readonly Red = new Enum('#FF0000');
  public static readonly Green = new Enum('#00FF00');
  public static readonly Blue = new Enum('#0000FF');
}

export class Color extends PrimaryColor {
  public static readonly White = new Enum('#FFFFFF');
  public static readonly Black = new Enum('#000000');
}

// Usage:

console.log(PrimaryColor.Red);
// Output: Enum { value: '#FF0000' }
console.log(Color.Red); // inherited!
// Output: Enum { value: '#FF0000' }
console.log(Color.Red.value); // we have to call .value to get the value.
// Output: #FF0000
console.log(Color.Red.toString()); // toString() works too.
// Output: #FF0000

class Thing {
  color: Color;
}

let thing: Thing = {
  color: Color.Red,
};

switch (thing.color) {
  case Color.Red: // ...
  case Color.White: // ...
}

@basarat的回答很棒。下面是一个你可以使用的简化但有点扩展的例子:

export type TMyEnumType = 'value1'|'value2';

export class MyEnumType {
    static VALUE1: TMyEnumType = 'value1';
    static VALUE2: TMyEnumType = 'value2';
}

console.log(MyEnumType.VALUE1); // 'value1'

const variable = MyEnumType.VALUE2; // it has the string value 'value2'

switch (variable) {
    case MyEnumType.VALUE1:
        // code...

    case MyEnumType.VALUE2:
        // code...
}

这对我来说很管用:

class MyClass {
    static MyEnum: { Value1; Value2; Value3; }
    = {
        Value1: "Value1",
        Value2: "Value2",
        Value3: "Value3"
    };
}

or

module MyModule {
    export var MyEnum: { Value1; Value2; Value3; }
    = {
        Value1: "Value1",
        Value2: "Value2",
        Value3: "Value3"
    };
}

8)

更新:在发布这篇文章后不久,我发现了另一种方法,但忘记发布更新(然而,上面已经有人提到过了):

enum MyEnum {
    value1 = <any>"value1 ", 
    value2 = <any>"value2 ", 
    value3 = <any>"value3 " 
}
//to access the enum with its string value you can convert it to object 
//then you can convert enum to object with proberty 
//for Example :

enum days { "one" =3, "tow", "Three" }

let _days: any = days;

if (_days.one == days.one)
{ 
    alert(_days.one + ' | ' + _days[4]);
}