javascript - Jquery Ajax 返回 400 BAD 请求

Question

我正在尝试将数据发送到我的本地数据库服务器，但是当我尝试发送时，我总是收到 400 Bad request 错误。

var studentEmail = "ali@gmail.com";
            var dataString = '&questionNumber='+ temp + '&answer='+ value + '&email='+ studentEmail;


            $.ajax({
            type: "POST",
            dataType:'json',
            url: "js/dbcon.php",
            data: JSON.stringify(dataString),
            processData: false,
            contentType: "application/json; charset=utf-8"
            });

这是php文件

<?php
$connection = mysql_connect("127.0.0.1", "root", "root"); // Establishing Connection with Server..
$db = mysql_select_db("db", $connection); // Selecting Database
//Fetching Values from URL
$questionNumber=$_POST['questionNumber'];
$answer=$_POST['answer'];
$email=$_POST['email'];
//Insert query
$query = mysql_query("INSERT INTO answers (questionNumber,studentAnswer,studentEmail) VALUES ($questionNumber,$answer,$email)");
echo "succesfully posted";
mysql_close($connection); // Connection Closed
?>

谁能看出我做错了什么？

提前致谢!

Answer 1

JSON.stringify() 方法用于将 javascript object 转换为 json 字符串。

所以 dataString 变量必须是一个 javascript object:

var data ={questionNumber:temp ,answer: value ,email:studentEmail};

Ajax

$.ajax({
    type: "POST",
    dataType:'json',
    url: "js/dbcon.php",
    data: JSON.stringify(data),
    processData: false,
    contentType: "application/json; charset=utf-8"
});