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
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]
);
}
其他回答
有一个简单的解决方案，当你运行object。Keys (Enum)它会给你一个值和键的数组，在第一个slice Values中，在第二个slice key中，为什么我们不直接返回第二个slice，下面的代码对我来说是有用的。
enum Enum {
ONE,
TWO,
THREE,
FOUR,
FIVE,
SIX,
SEVEN
}
const keys = Object.keys(Enum);
console.log(keys.slice(keys.length / 2));
在数组中获取enum值。
export enum DocumentationTypeEnum {
GDPR = 'GDPR',
HELP = 'HELP',
OTHER = 'OTHER',
FOOTER = 'FOOTER'
}
const keys = Object.keys(DocumentationTypeEnum);
console.log(keys); // Output : ["GDPR", "HELP", "OTHER", "FOOTER"]
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;
}
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 },
];
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。
