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
this worked for me :
export enum FeedBackType {
FEEDBACK1= 'FEEDBACK1',
FEEDBACK2= 'FEEDBACK2',
FEEDBACK3= 'FEEDBACK3',
}
-----------------------------------------------------------------
export function getTypeFeedBackList() {
let feedbackList: FeedBackType[] = [];
Object.keys(FeedBackType).map((key) => {
let strEnum = key as unknown as FeedBackType;
feedbackList.push(strEnum);
});
return feedbackList;
}
----------------------------------------------------------------
declare this :
public feedbackList: FeedBackType[] = [];
and after call your function in :
ngOnInit(): void {
this.feedbackList = getTypeFeedBackList();
console.log(this.feedbackList);
}
Happy coding ;)
其他回答
我很惊讶，在一个TypeScript线程中，没有人给出支持类型的有效TypeScript函数。下面是@user8363解决方案的变化:
const isStringNumber = (value: string) => isNaN(Number(value)) === false;
function enumToArray<T extends {}>(givenEnum: T) {
return (Object.keys(givenEnum).filter(isStringNumber) as (keyof T)[]).map(
(key) => givenEnum[key]
);
}
设enum变量为:
enum EnumName {
A = 1,
B = 2
};
那么列表是:
const list = Object.keys(Enum)
.filter((value => isNaN(Number(value)) === false))
.map(key => ({ id: key, value: Enum[key] }));
list的值为
list = [
{ id:1 , value: A },
{ id:2 , value: B },
];
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);
我已经解出来了。 假设您有一个如下所示的枚举
export enum UnitEnum {
GRAM = 'gm',
KILOGRAM = 'kg',
LITRE = 'lt',
CENTIMETER = 'cm',
INCH = 'in',
METER = 'mt',
KILOMETER = 'km',
}
你有这样一门课，
export interface Unit {
Name: string;
Symbol: string;
}
然后，您可以创建一个如下所示的函数，将异构枚举映射到某个类型的对象，
export function getDefaultUnits() {
const myUnits = Object.entries(UnitEnum).map(x => {
return { Name: x[0], Symbol: x[1] } as Unit
})
console.log(myUnits);
return myUnits;
}
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。
