javascript 获取某个 JSON 对象字段的值
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Getting a value of a certain JSON object field
提问by cycero
I have the following JSON object:
我有以下 JSON 对象：
var definitionsObject = {"company" : "Some information about company"};
This object will actually contain a lot of definitions, not just one. And I also have the following event handler for a link click which has a custom "data-name" attribute containing the term "company":
这个对象实际上会包含很多定义，而不仅仅是一个。而且我还有以下链接点击事件处理程序，它具有包含术语“公司”的自定义“数据名称”属性：
$(".definitinOpener").click(function() {
$this = $(this);
var hintID = $this.attr("data-name");
var hintText = definitionsObject.hintID;
});
So, what I'm trying to do is get the value of "data-name" custom attribute of the clicked link, go to the definitionsObjectobject and get the value of the field which is equal to the "data-name" attribute value. However in this way I'm always getting "undefined".
所以，我想要做的是获取单击链接的“数据名称”自定义属性definitionsObject的值，转到对象并获取等于“数据名称”属性值的字段值。然而，通过这种方式，我总是得到“未定义”。
Could anybody please help me to figure out what exactly I'm doing wrong?
有人可以帮我弄清楚我到底做错了什么吗？
Thank you beforehand.
先谢谢了。
回答by Kristoffer Sall-Storgaard
You can look up a value in an object in two ways.
您可以通过两种方式在对象中查找值。
var obj = { key : 'value' }
var lookup = 'key'
console.log( obj.lookup ) //undefined
console.log( obj.key ) //value
console.log( obj[lookup] ) //value
You probably want this:
你可能想要这个：
var hintText = definitionsObject[hintID];
回答by gbtimmon
definitionsObject.hintIDdoes not return definitionsObject[hintId], it will return definitionsObject['hintId'].
definitionsObject.hintID不返回definitionsObject[hintId]，它会返回definitionsObject['hintId']。
I belive you can accomplish this with
我相信你可以做到这一点
var hintText = definitionsObject[hintId];
instead of
代替
var hintText = definitionsObject.hintID;
