jQuery JSON 值在 javascript 中被解析为未定义
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JSON values parsed as undefined in javascript
提问by Riju Mahna
I am trying to parse a JSON in Javascript. The JSON is created as an ajax response:
我正在尝试用 Javascript 解析 JSON。JSON 被创建为 ajax 响应：
$.ajax(url, {
dataType: "text",
success: function(rawData, status, xhr) {
var data;
try {
data = $.parseJSON(rawData);
var counter = data.counter;
for(var i=1; i<=counter; i++){
//since the number of 'testPath' elements in the JSON depend on the 'counter' variable, I am parsing it in this way
//counter has the correct integer value and loops runs fine
var currCounter = 'testPath'+i ;
alert(data.currCounter); // everything alerts as undefined
}
} catch(err) {
alert(err);
}
},
error: function(xhr, status, err) {
alert(err);
}
});
But all values alert 'undefined' as value (except the 'counter' which gives correct value) The actual string as seen in firebug is as below:
但是所有值都警告“未定义”作为值（除了给出正确值的“计数器”）在萤火虫中看到的实际字符串如下：
{"testPath1":"ab/csd/sasa", "testPath2":"asa/fdfd/ghfgfg", "testPath3":"ssdsd/sdsd/sds", "counter":3}
回答by DhruvPathak
alert(data[currCounter]), this will work.
alert(data[currCounter])，这会起作用。
as data.currCounterlooks for the key 'currCounter` in the object, not by the value of currCounter.
asdata.currCounter在对象中查找键 'currCounter`，而不是通过 currCounter 的值。
example:
例子：
var myObj = { 'name':'dhruv','age':28 };
var theKey = 'age';
alert(myObj.theKey); // undefined
alert(myObj[theKey]); // 28
回答by sjkm
Use
用
alert(data[currCounter]);
instead. You cannot access a property like you did....
反而。您无法像以前那样访问属性....
回答by Sushanth --
Need to use []notation
需要使用[]符号
data[currCounter]
回答by user2059250
Try data[currCounter] because there is no value in data.currCount.
试试 data[currCounter]，因为 data.currCount 中没有值。
