转换收到的ajax数据的问题
[英]Issue in converting received ajax data
问题描述
Ajax is used to retrieve data from server. 
Ajax用于从服务器检索数据。
Data is displayed successfully on alert as 数据在警报时成功显示为
data: {"status": "Active","broadcastmsg": "msg"}
But in html ie <p id="demo"></p> it is displayed as undefined . 但是在html即<p id="demo"></p>它显示为未定义 。
Looks like a minor issue , though I have been trying to solve this since last 24 hours and nothing seems to be working. 看起来像一个小问题，虽然我一直试图解决这个问题，因为过去24小时似乎没有任何工作。 Please suggest what's going wrong. 请说明出了什么问题。
Client.php
<!DOCTYPE html>
<html>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<body>
<script>
function myFunction(val) {
$.post("test.php",
{
d_id: 1,
date: val
},
function(hstatus){
alert(hstatus);
myJSON = JSON.stringify(hstatus);
localStorage.setItem("testJSON", myJSON);
//Retrieving data:
text = localStorage.getItem("testJSON");
obj = JSON.parse(text);
document.getElementById("demo").innerHTML = obj.status;
});
}
</script>
<p id="demo"></p>
<div id="future_date" style="display:block;" class="col-xs-12">
<input type="date" name="txt" value="" onchange="myFunction(this.value)">
</div>
</body>
</html>
EDIT
if we pass hstatus = {"status": "Active","broadcastmsg": "msg"} manually it's showing result. 如果我们通过hstatus = {"status": "Active","broadcastmsg": "msg"}手动显示结果。
Thus issue is in converting from 因此，问题在于转换
data: {"status": "Active","broadcastmsg": "msg"}
to 至
{"status": "Active","broadcastmsg": "msg"}
4 个解决方案
解决方案1
2 已采纳 2017-06-08 11:24:17
Update: 更新：
If you have the "data: " part in front of the JSON data, you have to trim: 如果您在JSON数据前面有“data：”部分，则必须修剪：
myJSON = hstatus.substring(6);
see: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/String/substring 请参阅： https ： //developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/String/substring
Option A: You should include one more ( dataType ) parameter in the $.post call, so the jQuery knows the content type, otherwise you will get the response as plain text. 选项A：您应该在$.post调用中包含一个（ dataType ）参数，因此jQuery知道内容类型，否则您将以纯文本形式获得响应。 https://api.jquery.com/jquery.post/ https://api.jquery.com/jquery.post/
$.post("test.php", {
d_id: 1,
date: val
}, function() { /*...*/ },
"json");
You should also check your test.php and ensure that you are sending the Content-Type: application/json http header (see: http://php.net/manual/en/function.header.php ). 您还应检查test.php并确保发送Content-Type: application/json http标头（请参阅： http ： //php.net/manual/en/function.header.php ）。
Option B: (not recommended) Just remove the JSON.stringify() part from the callback function: 选项B :(不推荐）只需从回调函数中删除JSON.stringify()部分：
function(hstatus){
localStorage.setItem("testJSON", hstatus);
//Retrieving data:
text = localStorage.getItem("testJSON");
obj = JSON.parse(text);
document.getElementById("demo").innerHTML = obj.status;
});
Just a tip: 只是一个提示：
Use the console.log() command for debug variable values so you can see the exact, typed value in your browser console (press F12 in most browser). 使用console.log()命令调试变量值，以便在浏览器控制台中查看确切的类型值（在大多数浏览器中按F12键）。 The alert() function automatically converts everything into strings so it usually show misleading results. alert()函数自动将所有内容转换为字符串，因此通常会显示误导性结果。
解决方案2
1 2017-06-08 11:54:17
What I suspect is the format of string which is coming from server. 我怀疑是来自服务器的字符串格式。
if your alert is giving this output: data: {"status": "Active","broadcastmsg": "msg"} Then JSON.parse won't be able to parse it. 如果您的警报提供此输出：data：{“status”：“Active”，“broadcastmsg”：“msg”}然后JSON.parse将无法解析它。 Since it's not an object or any type. 因为它不是一个对象或任何类型。 This will give a syntax error. 这将产生语法错误。
Following is the right format of string which you should send from server then everything JSON.parse will work fine. 以下是您应该从服务器发送的正确格式的字符串，然后JSON.parse可以正常工作。 {"data": {"status": "Active","broadcastmsg": "msg"}} {“data”：{“status”：“Active”，“broadcastmsg”：“msg”}}
So solution for this which I can guess is: hstatus parameter of success callback is of plainObject So try following: 所以我可以猜到的解决方案是：成功回调的hstatus参数是plainObject所以请尝试以下方法：
myJSON = JSON.stringify(hstatus.data);
Let me know in case it doesnt work, will dig more. 让我知道，如果它不起作用，将挖掘更多。
解决方案3
0 2017-06-08 10:59:23
你可以试试这个：
document.getElementById("demo").innerHTML = obj.data.status;
解决方案4
0 2017-06-08 10:59:48
您需要通过obj.data.status而不是obj.status访问您的status属性
document.getElementById("demo").innerHTML = obj.data.status;
声明:本站的技术帖子网页，遵循CC BY-SA 4.0协议，如果您需要转载，请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.