不同的价值添加到同一个对象的JavaScript字面 [英] Add different value to the same object literal javascript

问题描述

我有一块code来创建一个对象字面数​​组。该阵列由2其他字符串数组创建的，一会成为对象文本 colHeads 和其他阵列将数据 dataArr 。

I have a piece of code to create an object literal array. The array is created from 2 other string array, one will become the object literal colHeads and the other array will be the data dataArr.

colHeads = [名称，状态]

dataArr = [约翰·A·史密斯，琼·琼斯]

var temp = [];
var tempObj = {};

for (var i=0; i<colHeads.length; ++i) { // columns
    var dataArr = colDatas[i].split(",");
    for (var j = 0; j < dataArr.length; j++) { // data
        tempObj[colHeads[i]] = dataArr[j];
    }
    temp.push(tempObj);
}

最后阵列应该是这样的：

The final array should look like this:

var data = [
      {name: 'John A. Smith', state: 'CA'},
      {name: 'Joan B. Jones', state: 'NY'}
    ];

下面的问题是根据该行 TEMPOBJ [colHeads [I] = dataArr [0]; 对象常量会在两个数组中的最后一项更换的使结果是这样的：

Problem here is according to this line tempObj[colHeads[i]] = dataArr[0]; The object literal would be replaced with the last entry in both arrays which make the result look like this:

var data = [
      {name: 'Joan B. Jones', state: 'NY'},
      {name: 'Joan B. Jones', state: 'NY'}
    ];

我是新来的JavaScript，所以我不知道很多语法

I'm new to javascript so I don't know much the syntax

推荐答案

首先，你的循环访问相同dataArr指数，它应该使用Ĵ

First off, your loop is accessing the same dataArr index, it should be using j

tempObj[colHeads[i]] = dataArr[j];

二，你是不是建设新tempObjs每个回路，所以每个项目指标股同样TEMPOBJ这将最终让你有完全相同的对象列表。

Second, you are not constructing new tempObjs for each loop, so each item index shares the same tempObj which will end up leaving you with a list of the same exact object.

到目前为止，您的code看起来应该是这样的东西更多：

So far your code should look something more like this:

var temp = [];

for (var i=0; i<colHeads.length; ++i) { // columns
  var tempObj = {};
  var dataArr = colDatas[i].split(",");
  for (var j = 0; j < dataArr.length; j++) { // data
    tempObj[colHeads[j]] = dataArr[j];
  }
  temp.push(tempObj);
}

最后，我们会根据每列制作一个TEMPOBJ，而不是每一行，你应该做的。

Lastly, You are only creating one tempObj for each column, rather than each row as you should be doing.

var temp = [];
var rowCount = colDatas[0].split(',').length;
for (var i = 0; i < rowCount; ++i) { // rows first
  var tempObj = {};
  for (var j = 0; j < colHeads.length; ++j) { // now columns
    tempObj[colheads[j]] = colDatas[j].split(',')[i];
  }
  temp.push(tempObj);
}

现在，由于设置你的colDatas对象的方式，它要求你将它们分割为每循环，可以成为pretty昂贵的，我建议你找到另一种方式来存储它们，让它们能够更好的优化。

Now, due to the way your colDatas object is set up, it requires you to split them for every loop which can become pretty costly, I suggest you find another way to store that so it can be better optimized.

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