1.前臺設定contentType:"application/x-www-form-urlencoded"，前臺是JSON物件，後臺接收方法可以是字串、物件。示例如下：

function remoteService(url,postData)
{
var res = "";
$.ajax({
                cache: true,
                type: "POST",
                url:url,
                data:{"userID":"1","userName":"chenxk1","lastLoginTme":"2017-05-03","isDelete":1,"password":"chenxk"},    
                contentType:"application/x-www-form-urlencoded",
                async: false,
                error: function(request) {
                res="Connection error";
                },
                success: function(data) {
                   res = data;
                }
            });
return res;
}

@RequestMapping(value="/listOneUser", method = { RequestMethod.POST })
public JSONObject  getOneUser(String str)
{
User user = new User();
user.setUserID("-1");
user.setIsDelete(0);
user.setUserName("<p>chenxk</p>sadasd<img src='/upload/1.png'></img>");
System.out.println(user);

return JsonUtils.returnJsonObject(user);
//return "123";
}

或者

@RequestMapping(value="/listOneUser", method = { RequestMethod.POST })
public JSONObject  getOneUser(User user )
{

System.out.println(user);

return JsonUtils.returnJsonObject(user);
//return "123";
}

2.前臺設定contentType:"application/json"的話，前臺必須是JSON字串，後臺只能使用@RequestBody接收引數 function remoteService(url,postData)
{
var res = "";
$.ajax({
                cache: true,
                type: "POST",
                url:url,
                data:JSON.stringify({"userID":"1","userName":"chenxk1","lastLoginTme":"2017-05-03","isDelete":1,"password":"chenxk"}),      //這是引數是字串啊啊
                contentType:"application/x-www-form-urlencoded",
                async: false,
                error: function(request) {
                res="Connection error";
                },
                success: function(data) {
                   res = data;
                }
            });
return res;
}
後臺必須是@RequestBody User @RequestMapping(value="/listOneUser", method = { RequestMethod.POST })
public JSONObject  getOneUser(@RequestBody User)
{

user.setUserID("-1");
user.setIsDelete(0);
user.setUserName("<p>chenxk</p>sadasd<img src='/upload/1.png'></img>");
System.out.println(user);

return JsonUtils.returnJsonObject(user);
//return "123";
}