前言
最近在使用java接收前臺$.ajax數據格式爲多維json數組數據時，遇到了一個問題，問題例子如下：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script src="jquery-1.7.2.js"></script>
<script>
//前臺代碼如下
$(document).ready(function(){
$('#btn').click(function(){
//obj爲多維json數組數據格式
var obj={
name:'key',
age:18,
sex:'男',
info:{
qq:'123456',
email:'[email protected]',
girlFriend:{
name:'lucy',
age:18,
sex:'女'
}
}
};
$.ajax({
type:'post',
url:'Test',
data:obj,
dataType:'json',
success:function(data){
console.log(data);
}
});
});
});
</script>
</head>
<body>
<button id="btn">按鈕</button>
</body>
</html>後臺java代碼如下：
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();
System.out.println(request.getParameter("name"));//key
System.out.println(request.getParameter("age"));//18
//一維數據如：name、age、sex等都可以通過request.getParameter獲取到，當獲取二維數據"info"時卻打印爲null
System.out.println(request.getParameter("info"));//null
out.flush();
out.close();
}原因
因爲前臺ajax的XMLHttpRequest對象send()方法（post方式）發送數據的數據格式應爲send(“name=key&age=18&sex=男”)，卻不能是這樣的send(“…sex=男&info={…}”)即（不能爲info={…}）。但是php卻能成功的接收到，而java卻爲null，這裏暫時將原因歸咎於java對數據的解析問題，如果有讀者知道根本原因還請評論留言給我，感激不盡。
解決方法
前臺代碼如下：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script src="jquery-1.7.2.js"></script>
<script>
$(document).ready(function(){
$('#btn').click(function(){
//將多維數據的值設爲json格式的字符串
/*var obj={
name:'key',
age:18,
sex:'男',
info:"{qq:'123456',email:'[email protected]',girlFriend:{name:'lucy',age:18,sex:'女'}}"
}*/
//或者爲這樣（可以調用JSON.stringify(jsonObj)轉換爲字符串），整個用request.getParameter("data")接收
var obj={data:"{name:'key',age:18,sex:'男',info:{qq:'123456',email:'[email protected]',girlFriend:{name:'lucy',age:18,sex:'女'}}}"}
$.ajax({
type:'post',
url:'Test',
data:obj,
dataType:'json',
success:function(data){
console.log(data);
}
});
});
});
</script>
</head>
<body>
<button id="btn">按鈕</button>
</body>
</html>後臺代碼如下：
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setContentType("text/plain;charset=utf-8");
PrintWriter out = response.getWriter();
System.out.println(request.getParameter("data"));
JSONObject strJson = parseStr(request.getParameter("data"));
try {
System.out.println(strJson.getString("name"));//key
System.out.println(strJson.getString("age"));//18
System.out.println(strJson.getString("info"));
//{"email":"[email protected]","girlFriend":{"sex":"女","age":18,"name":"lucy"},"qq":"123456"}
out.write(strJson.getString("info"));
} catch (JSONException e) {
e.printStackTrace();
}
out.flush();
out.close();
}
public JSONObject parseStr(String str) {
try {
return new JSONObject(str);
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}其中用到的是：
java的json數據解析jar包[點擊下載]
jar包導入方法可根據自己的編輯器自行百度