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
另一种方法是使用ES8 Object.entries
export enum Weeks {
MONDAY = 1,
TUESDAY= 2,
WEDNESDAY = 3,
THURSDAY = 4,
FRIDAY = 5,
SATURDAY=6,
SUNDAY=7,
}
function convertEnumToArray(){
const arrayObjects = []
// Retrieve key and values using Object.entries() method.
for (const [propertyKey, propertyValue] of Object.entries(Weeks)) {
// Ignore keys that are not numbers
if (!Number.isNaN(Number(propertyKey))) {
continue;
}
// Add keys and values to array
arrayObjects.push({ id: propertyValue, name: propertyKey });
}
console.log(arrayObjects);
}
将产生以下内容:
[
{ id: 1, name: 'MONDAY' },
{ id: 2, name: 'TUESDAY' },
{ id: 3, name: 'WEDNESDAY' },
{ id: 4, name: 'THURSDAY' },
{ id: 5, name: 'FRIDAY' },
{ id: 6, name: 'SATURDAY' },
{ id: 7, name: 'SUNDAY' }
]
无耻地从这个博客偷来的
其他回答
我不喜欢上面的答案，因为它们都不能正确地处理字符串/数字的混合，可以在TypeScript enum中作为值。
下面的函数遵循TypeScript枚举的语义，给出键到值的正确映射。从那里，获取一个对象数组或者仅仅是键或者仅仅是值是很简单的。
/**
* Converts the given enum to a map of the keys to the values.
* @param enumeration The enum to convert to a map.
*/
function enumToMap(enumeration: any): Map<string, string | number> {
const map = new Map<string, string | number>();
for (let key in enumeration) {
//TypeScript does not allow enum keys to be numeric
if (!isNaN(Number(key))) continue;
const val = enumeration[key] as string | number;
//TypeScript does not allow enum value to be null or undefined
if (val !== undefined && val !== null)
map.set(key, val);
}
return map;
}
使用示例:
enum Dog {
Rover = 1,
Lassie = "Collie",
Fido = 3,
Cody = "Mutt",
}
let map = enumToMap(Dog); //Map of keys to values
let objs = Array.from(map.entries()).map(m => ({id: m[1], name: m[0]})); //Objects as asked for in OP
let entries = Array.from(map.entries()); //Array of each entry
let keys = Array.from(map.keys()); //An array of keys
let values = Array.from(map.values()); //An array of values
我还要指出OP是逆向思考枚举的。枚举中的“键”在技术上是在左边，而值在右边。TypeScript允许你尽可能多地重复RHS上的值。
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]); ｝
首先，我们得到这个枚举的键数组。然后，使用map()函数将数据转换为所需的格式。Id从键获取，name从enum通过相同的键获取。
const converted = Object.keys(GoalProgressMeasurements).map(key => {
return {
id: GoalProgressMeasurements[key],
name: key,
};
});
只有一句话:
Object.entries(GoalProgressMeasurements).map(([key, value]) => ({id: key, value: value}))
enum目标进度测量{ 百分比= 1， Numeric_Target = 2， Completed_Tasks = 3， average_milestone one_progress = 4， Not_Measured = 5 ｝ Const数组= [] for (const [key, value] of Object.entries(GoalProgressMeasurements)) { if (!Number. isnan (Number(key)) { 继续; ｝ 数组中。Push ({id:值，名称:键。Replace ('_'， ")}); ｝ console.log(数组);
