从typescript中的对象数组中获取属性值数组

Question

class Test{
    constructor(private Name: string, private Id: number, private isAlive: boolean){}

    array1?: string[];
}

想象一下，使用API​​响应中的一堆数据初始化数组。我有一组Test对象。我现在需要的是将该数组中所有这些对象的名称提取到一个新数组中。我找不到这个问题的typescript语法。

Answer 1

我现在需要的是将该数组中所有这些对象的名称提取到一个新数组中

使用Array.prototype.map：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map

Fix

从Name[]你想要string[]：

const array1: string[] = names.map(x=>x.fieldThatIsTheStringYouWant);

Answer 2

Typescript（或多或少）是javascript的超集。 Javascript的相同解决方案将适用于Typescript。

const output = input.map( item => item.name );

Answer 3

  var originalObject = [
        {"first":"Gretchen","last":"Kuphal","email":"[email protected]","address":"416 
                            Lesch Road","created":"March 1, 2012","balance":"$9,782.26"}];

1.你想简单地复制数组

var duplicateObject = originalObject;

2. 如果你想要所有你可以循环
3. 如果您想访问一个值，只需执行此操作即可

duplicateObject[0].first

alert(duplicateObject[0].first);

Editrd也可以这样做

var originalObject = [
  {"first":"Gretchen","last":"Kuphal","email":"[email protected]","address":"416 Lesch Road","created":"March 1, 2012","balance":"$9,782.26"},
{"first":"Morton","last":"Mayer","email":"[email protected]","address":"1602 Bernhard Parkway","created":"April 29, 2017","balance":"$6,596.11"},
{"first":"Catalina","last":"Daugherty","email":"[email protected]","address":"11893 Kali Vista","created":"October 16, 2008","balance":"$6,372.86"},
{"first":"Orpha","last":"Heaney","email":"[email protected]","address":"8090 Chris Stream","created":"November 21, 2015","balance":"$9,596.26"},
{"first":"Reva","last":"Mohr","email":"[email protected]","address":"0291 Kailyn Stravenue","created":"November 6, 2014","balance":"$4,768.37"},
{"first":"Loma","last":"Keeling","email":"[email protected]","address":"84460 Samson Knoll","created":"June 13, 2017","balance":"$9,361.16"}
];

var duplicateObject=new Array(); 

for (let num of originalObject) {
    duplicateObject.push(num.first);
}
// print
for (let first of duplicateObject) {
    console.log(first);
}