我有一个这样定义的枚举:

export enum GoalProgressMeasurements {
    Percentage = 1,
    Numeric_Target = 2,
    Completed_Tasks = 3,
    Average_Milestone_Progress = 4,
    Not_Measured = 5
}

然而,我希望它被表示为一个对象数组/列表从我们的API如下:

[{id: 1, name: 'Percentage'}, 
 {id: 2, name: 'Numeric Target'},
 {id: 3, name: 'Completed Tasks'},
 {id: 4, name: 'Average Milestone Progress'},
 {id: 5, name: 'Not Measured'}]

是否有简单和本地的方法来做到这一点,或者我必须构建一个函数,将枚举转换为int和字符串,并将对象构建为数组?


当前回答

该方法基于语句: enum的键不能是数字

export const isNumeric = (num?: Value | null): num is number => {
  if (num === undefined || num === null) {
    return false;
  } 
  
  const number = +num;

  if (number - number !== 0) {
    // Discard Infinity and NaN
    return false;
  }

  if (number === num) {
    return true;
  }

  if (typeof num === 'string') {
    return !(number === 0 && num.trim() === '');
  }
  return false;
};

enum En  {
  ewq1 = 1,
  we2 = 'ss',
  sad = 'sad',
}

type TEnum = {
    [id: string]: number | string;
}

export const getEnumValues = <T extends TEnum>(enumerable: T) =>
  Object.keys(enumerable)
    .filter((x) => !isNumeric(x))
    .map((key) => enumerable[key] as T[keyof T]) 

console.log(getEnumValues(En)) // [1, "ss", "sad"] 

其他回答

简单的解决方案。您可以使用以下函数将Enum转换为对象数组。

 buildGoalProgressMeasurementsArray(): Object[] {

    return Object.keys(GoalProgressMeasurements)
              .map(key => ({ id: GoalProgressMeasurements[key], name: key }))
 }

如果你需要去掉下划线,我们可以像下面这样使用regex:

buildGoalProgressMeasurementsArray(): Object[] {

    return Object.keys(GoalProgressMeasurements)
              .map(key => ({ id: GoalProgressMeasurements[key], name: key.replace(/_/g, ' ') }))
 }
function enumKeys(_enum) {
  const entries = Object.entries(_enum).filter(e => !isNaN(Number(e[0])));
  if (!entries.length) {
    // enum has string values so we can use Object.keys
    return Object.keys(_enum);
  }
  return entries.map(e => e[1]);
}

你可以这样做:

export enum GoalProgressMeasurements {
    Percentage = 1,
    Numeric_Target = 2,
    Completed_Tasks = 3,
    Average_Milestone_Progress = 4,
    Not_Measured = 5
}

export class GoalProgressMeasurement {
    constructor(public goalProgressMeasurement: GoalProgressMeasurements, public name: string) {
    }
}

export var goalProgressMeasurements: { [key: number]: GoalProgressMeasurement } = {
    1: new GoalProgressMeasurement(GoalProgressMeasurements.Percentage, "Percentage"),
    2: new GoalProgressMeasurement(GoalProgressMeasurements.Numeric_Target, "Numeric Target"),
    3: new GoalProgressMeasurement(GoalProgressMeasurements.Completed_Tasks, "Completed Tasks"),
    4: new GoalProgressMeasurement(GoalProgressMeasurements.Average_Milestone_Progress, "Average Milestone Progress"),
    5: new GoalProgressMeasurement(GoalProgressMeasurements.Not_Measured, "Not Measured"),
}

你可以这样使用它:

var gpm: GoalProgressMeasurement = goalProgressMeasurements[GoalProgressMeasurements.Percentage];
var gpmName: string = gpm.name;

var myProgressId: number = 1; // the value can come out of drop down selected value or from back-end , so you can imagine the way of using
var gpm2: GoalProgressMeasurement = goalProgressMeasurements[myProgressId];
var gpmName: string = gpm.name;

您可以根据需要使用对象的附加属性扩展GoalProgressMeasurement。我将这种方法用于每个应该是包含多个值的对象的枚举。

export function enumKeys(E: any): string[] {
    return Object.keys(E).filter(k => isNaN(Number(k)));
}

export function enumValues(E: any): string[] | number[] {
    return enumKeys(E).map(k => E[k as any]);
}

两者都适用:

enum TestA {
    RED = "red",
    BLUE = "blue"
}

enum TestB {
    ONE = 1,
    TWO = 2
}

由于具有字符串值的枚举不同于具有数字值的枚举,因此最好从@user8363解决方案中过滤非数字。

这里是你如何从enum字符串中获取值,数字混合:

/ /帮助 export const StringIsNotNumber = value => isNaN(Number(value)) === true; //将枚举转换为数组 导出函数enumToArray(枚举){ 返回种(enumme) .filter (StringIsNotNumber) .map(key => enumme[key]); }