Question

此代码查找javascript对象中“ AL”的位置，然后搜索“ AL”的位置以查找与“ AL”相关的其他属性，例如宽度。

为什么此代码返回对象中最后一项的宽度，而不是“ AL”的宽度？

我可以成功编码位置[0]，但我希望将位置编码为变量[z]

myObj = {
  "type":"A",
  "info": [
    { "item":"1", "properties":{ "id":"AL", "height": "25", width: "50" } },
    { "item":"2", "properties":{ "id":"PO", "height": "30", width: "40" } },
    { "item":"3", "properties":{ "id":"RA", "height": "20", width: "100" } }
  ]
}


myObj.info.forEach(function(e, z) {
  if (e.properties.id == "AL") document.getElementById("position").innerHTML = z;
  document.getElementById("width").innerHTML = myObj.info[z].properties.width;
});

<p>Position in object:<span id="position"></span></p>

<p>Width:<span id="width"></span></p>

Answer 1

使用代码块更改if语句，以便最后一条语句将在if语句内执行

myObj = {
  "type":"A",
  "info": [
    { "item":"1", "properties":{ "id":"AL", "height": "25", width: "50" } },
    { "item":"2", "properties":{ "id":"PO", "height": "30", width: "40" } },
    { "item":"3", "properties":{ "id":"RA", "height": "20", width: "100" } }
  ]
}


myObj.info.forEach(function(e, z) {
  if (e.properties.id == "AL") {
    document.getElementById("position").innerHTML = z;
    document.getElementById("width").innerHTML = myObj.info[z].properties.width;
  }
  
});

<p>Position in object:<span id="position"></span></p>

<p>Width:<span id="width"></span></p>

使用javascript对象的position变量查找相关属性

1 个答案: