如何使用Typescript中的值创建和解析字符串枚举

Question

I know that there is issue with creating string enums using Typescript, even in v2.4+ I'm using typescript 2.8 and Angular 6.

I would like to have an enum and to freely get string value from enum, and to parse string into enum.

So assume I have this enum:

export enum MyEnum{
  INIT = 'init-room',
  CLOSE = 'close-room'
}

This enum is useful to communicate with rest API. So from API and to API I have to send strings. But inside app I want to asap convert string from API to enum.

So I want to have function to parse, and stringify my enum.

I try this approach, but this won't work.

export function toString(type: MyEnum): string {
    return MyEnum[type];
}

export function parse(type: string): Mode {
    return MyEnum[type];
}

Well, it isn't big surprise, because I want to get value from this enum, not MyEnum[type] - but I don't know how to do this.

I know that there is an issue with converting key to value, while value to key works. So I'm asking for any clean-code solution to achieve my goal.

Answer 1

也许尝试获得这样的价值：

return MyEnum.type;

Answer 2

Try the following:

enumValues(enumType:any):number[] {
    return Object.keys(enumType).map(k => enumType[k]).filter(v => typeof v === "number")
}

enumString(enumType:any, enumValue:any):string {
    return enumType[enumValue];
}

Answer 3

您可以安全地切换到常量。