使用泛型将字符串转换为枚举

Question

How can I convert a string to Enum using generics in TypeScript?

export function getMethodEnum<T>(actionStr: string): T
{
    return actionStr as T; // does not work
}

export enum ActionEnum {
    Unknown = 0,
    Sleep = 1,
    Run
}

let action: ActionEnum = getMethodEnum<ActionEnum>()

Answer 1

You need to send the actual enum object to the function, since you want to map the string name of the enum to the value. This relation is stores in the enum object itself.

function getMethodEnum<T>(enumObject: T, actionStr: string): T[keyof T]
{
    return enumObject[actionStr as keyof T];
}

enum ActionEnum {
    Unknown = 0,
    Sleep = 1,
    Run
}

let action: ActionEnum = getMethodEnum(ActionEnum, "Sleep");