Question

我正在学习ES6和对象，并且想知道如何摆脱这种对象数组中的一个键值对：

[
    { "name" : "mark", "height" : "tall", "theId" : "1", "nat" : "uk"},
    { "name" : "ben", "height" : "medium", "theId" : "2", "nat" : "uk"},
    { "name" : "neil", "height" : "small", "theId" : "3", "nat" : "uk" }
]

结果应为：

[
    { "name" : "mark", "height" : "tall", "nat" : "uk"},
    { "name" : "ben", "height" : "medium", "nat" : "uk"},
    { "name" : "neil", "height" : "small", "nat" : "uk" }
]

我创建了一个forEach函数，并尝试将每个结果推送到一个新数组中，但是现在没有对象。

如何解决？还是有更好的方法使用ES6 / ES7语法做到这一点？谢谢你的帮助。代码和codePen URL如下：

Codepen：https://codepen.io/anon/pen/bPYQyb

let objArr = [
	{ "name" : "mark", "height" : "tall", "theId" : "1", "nat" : "uk"},
	{ "name" : "ben", "height" : "medium", "theId" : "2", "nat" : "uk"},
	{ "name" : "neil", "height" : "small", "theId" : "3", "nat" : "uk" }
],
    arr = [];

objArr.forEach(function(obj) {
	for (let column in obj) {
      let currArr = [];
    if (isNaN(obj[column])) {
      console.log('true');
      currArr.push(obj[column]);
    }
    arr.push(currArr);
  }
});

console.log(arr);

Answer 1

objArr.forEach(a => delete a.theId);

用于删除运算符的文档：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/delete

Answer 2

只需删除密钥：

let objArr = [
	{ "name" : "mark", "height" : "tall", "theId" : "1", "nat" : "uk"},
	{ "name" : "ben", "height" : "medium", "theId" : "2", "nat" : "uk"},
	{ "name" : "neil", "height" : "small", "theId" : "3", "nat" : "uk" }
];


objArr.forEach(function(obj) {
	delete obj.theId;
});

console.log(objArr);

Answer 3

如果要就地修改当前对象，则可以遍历数组中的对象并使用delete <name_of_key>;语句（doc here）。即使对象中不存在密钥，也可以安全使用。

所以你可以做

for (let obj of objArr) {
  delete obj.theId;
}

或功能方式

objArr.forEach(obj => delete obj.theId);

Answer 4

如果使用immutability is important，则一种方法是将.map()中的每个项目objArray转换为新的arr数组，在该数组中，您可以在地图回调期间过滤掉键为"theId"的条目。

要过滤掉"theId"键，通过item循环迭代当前正在映射的for(.. in ..)的键，请检查key是否不是{{1} }，如果是这样，请将其及其值（即"thisId"）添加到新对象中：

item[key]

Answer 5

只需将destructuring和spreading与map一起使用，并隐式返回arrow function：

let objArr = [{"name":"mark","height":"tall","theId":"1","nat":"uk"},{"name":"ben","height":"medium","theId":"2","nat":"uk"},{"name":"neil","height":"small","theId":"3","nat":"uk"}];

const res = objArr.map(({ theId, ...r }) => r);

console.log(res);

.as-console-wrapper { max-height: 100% !important; top: auto; }

Answer 6

尝试一下：

var list = new List<KeyValuePair<string, string>>() { 
                new KeyValuePair<string, string>("Value", 0),
                new KeyValuePair<string, string>("Value1", 79),

如何从数组内的所有对象中删除一个简单的特定键值对

6 个答案: