Question

我有一个带有对象数组的简单json，我设法提取了记录，但是它带有方括号，我只想要对象。

var res = {
  "totalSize": 3,
  "done": true,
  "records": [{
    "Id": "1",
    "CaseNumber": "1",
    "Subject": "test1"
  }, {
    "Id": "2",
    "CaseNumber": "2",
    "Subject": "test2"
  }, {
    "Id": "3",
    "CaseNumber": "3",
    "Subject": "test3"
  }]
}

var extractedRecord = res.records.slice(0, 1);

所需结果：

  {
    "Id": "1",
    "CaseNumber": "1",
    "Subject": "test1"
  }

实际结果：

[
  {
    "Id": "1",
    "CaseNumber": "1",
    "Subject": "test1"
  }
]

请参阅此jsfiddle。

Answer 1

只需res.records.slice(0, 1)[0]

var res = {"totalSize":3,"done":true,"records":[{"Id":"1","CaseNumber":"1","Subject":"test1"},{"Id":"2","CaseNumber":"2","Subject":"test2"},{"Id":"3","CaseNumber":"3","Subject":"test3"}]}

var extractedRecord = res.records.slice(0, 1)[0];
console.log(extractedRecord);

您还可以使用传播语法：

var res = {"totalSize":3,"done":true,"records":[{"Id":"1","CaseNumber":"1","Subject":"test1"},{"Id":"2","CaseNumber":"2","Subject":"test2"},{"Id":"3","CaseNumber":"3","Subject":"test3"}]}

var extractedRecord = res.records.slice(0, 1);
console.log(...extractedRecord);

Answer 2

Arrray.prototype.slice()，如其documention所述，从原始数组返回一个新数组。

根据MDN（我的重点）：

slice（）方法返回数组一部分的浅表副本放入从开始到结束选择的新数组对象（不包括结束）其中begin和end表示该数组中项目的索引。的原始数组将不会被修改。

知道这一点，得到一个返回的数组也就不足为奇了（即，用[和]包围的对象）。因此，您只需要提取其中的唯一项目：

var extractedRecord = res.records.slice(0, 1)[0];

Answer 3

尝试此代码。它将对您有用。

var res = {"totalSize":3,"done":true,"records":[{"Id":"1","CaseNumber":"1","Subject":"test1"},{"Id":"2","CaseNumber":"2","Subject":"test2"},{"Id":"3","CaseNumber":"3","Subject":"test3"}]}

const data = res.records[0]
console.log(data);

如何从JSON中的对象数组中提取对象？

3 个答案: