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
枚举是运行时存在的真实对象。所以你可以这样反向映射:
let value = GoalProgressMeasurements.Not_Measured;
console.log(GoalProgressMeasurements[value]);
// => Not_Measured
基于此，您可以使用以下代码:
export enum GoalProgressMeasurements {
Percentage = 1,
Numeric_Target = 2,
Completed_Tasks = 3,
Average_Milestone_Progress = 4,
Not_Measured = 5
}
let map: {id: number; name: string}[] = [];
for(var n in GoalProgressMeasurements) {
if (typeof GoalProgressMeasurements[n] === 'number') {
map.push({id: <any>GoalProgressMeasurements[n], name: n});
}
}
console.log(map);
参考:https://www.typescriptlang.org/docs/handbook/enums.html
其他回答
我使用
Object.entries(GoalProgressMeasurement).filter(e => !isNaN(e[0]as any)).map(e => ({ name: e[1], id: e[0] }));
一条简单的线就可以做到这一点。
它只需要3个简单的步骤 -使用Object.entries加载键和值的组合。 -过滤掉非数字(因为typescript会为反向查找生成值)。 -然后我们将它映射到我们喜欢的数组对象。
这将返回一个枚举值数组:
Object.values(myEnum);
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"]
枚举是运行时存在的真实对象。所以你可以这样反向映射:
let value = GoalProgressMeasurements.Not_Measured;
console.log(GoalProgressMeasurements[value]);
// => Not_Measured
基于此，您可以使用以下代码:
export enum GoalProgressMeasurements {
Percentage = 1,
Numeric_Target = 2,
Completed_Tasks = 3,
Average_Milestone_Progress = 4,
Not_Measured = 5
}
let map: {id: number; name: string}[] = [];
for(var n in GoalProgressMeasurements) {
if (typeof GoalProgressMeasurements[n] === 'number') {
map.push({id: <any>GoalProgressMeasurements[n], name: n});
}
}
console.log(map);
参考:https://www.typescriptlang.org/docs/handbook/enums.html
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 },
];
