jquery+ajax+php 实现注册（报名）

$('#sign').click(function() {
        alert('sign');
        var prodType = $('#prodType').val();
        var prodName = $("#prodName").val();
        var member = $("#member").val();
        var teacher = $("#teacher").val();
        var telephone = $("#telephone").val();
        var school = $("#school").val();
        if (prodType == '' || prodName == '' || member == '' || teacher == '' || telephone == '' || school == '') {
             alert("所有数据均必填");
         }else{
       if (telephone.length == 11) {
            $.ajax({
                type: "POST",
                url: "testDb.php",
                dataType: "JSON",
                data: {
                    "prodType": prodType,
                    "prodName": prodName,
                    "member": member,
                    "teacher": teacher,
                    "telephone": telephone,
                    "school": school,
                },
                success: function(data) {
                    switch (data) {
                        case 1: //用户已存在
                            alert("报名成功")
                            break;
                        case 0: //注册成功
                            alert("报名失败")
                            break;
                    }
                }
            })
        } else {
            alert('请检查您的联系方式');
        }
      }     
    })

<?php
header("charset=UTF-8");
$prodType = $_POST['prodType'];
$prodName=$_POST['prodName'];
$member=$_POST['member'];
$teacher=$_POST['teacher'];
$telephone=$_POST['telephone'];
$school=$_POST['school'];
$servername = "localhost";
$username = "root";
$password = "root";
$db = "league";
// 创建连接
try {
    $conn = new mysqli($servername, $username, $password,$db);
    $insert = $conn->prepare("INSERT INTO league VALUES (?, ?, ?, ?,?,?)");  
    $insert->bind_param('ssssss', $prodType,$prodName,$member,$teacher,$telephone,$school);  //防止sql注入
    $insert->execute();
    echo 1;
} catch (Exception $e) {
    echo 0;
}