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
class EnumHelpers {
static getNamesAndValues<T extends number>(e: any) {
return EnumHelpers.getNames(e).map(n => ({ name: n, value: e[n] as T }));
}
static getNames(e: any) {
return EnumHelpers.getObjValues(e).filter(v => typeof v === 'string') as string[];
}
static getValues<T extends number>(e: any) {
return EnumHelpers.getObjValues(e).filter(v => typeof v === 'number') as T[];
}
static getSelectList<T extends number, U>(e: any, stringConverter: (arg: U) => string) {
const selectList = new Map<T, string>();
this.getValues(e).forEach(val => selectList.set(val as T, stringConverter(val as unknown as U)));
return selectList;
}
static getSelectListAsArray<T extends number, U>(e: any, stringConverter: (arg: U) => string) {
return Array.from(this.getSelectList(e, stringConverter), value => ({ value: value[0] as T, presentation: value[1] }));
}
private static getObjValues(e: any): (number | string)[] {
return Object.keys(e).map(k => e[k]);
}
}
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);
一个棘手的地方是TypeScript会在触发对象中'double'映射enum，所以它可以通过键和值访问。
enum MyEnum {
Part1 = 0,
Part2 = 1
}
将以
{
Part1: 0,
Part2: 1,
0: 'Part1',
1: 'Part2'
}
所以你应该在映射之前先过滤对象。所以@Diullei的解决方案是正确的。这是我的实现:
// Helper
const StringIsNumber = value => isNaN(Number(value)) === false;
// Turn enum into array
function ToArray(enumme) {
return Object.keys(enumme)
.filter(StringIsNumber)
.map(key => enumme[key]);
}
像这样使用它:
export enum GoalProgressMeasurements {
Percentage,
Numeric_Target,
Completed_Tasks,
Average_Milestone_Progress,
Not_Measured
}
console.log(ToArray(GoalProgressMeasurements));
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]); ｝
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
