Question

我正在使用jQuery和PHP使用AJAX开发一个简单的注册页面。

以下是进行ajax调用的脚本：

<script>
    function submitForm(){
      var data1=$('#regform').serialize();
      $.ajax({
        type:'POST',
        url:'signup.php',
        data:data1,
        success: function(response){
          console.log(response);
          if(response==1)
            alert('taken');
            else if(response==2)
              alert('registered');
              else
                alert(response);
        }
      });
    }
  </script>

以及响应该调用的PHP脚本：

signup.php：

<?php
require_once 'dbconnect.php';
if($_POST) {
    $user_name = $_POST['user_name'];
    $user_email = $_POST['user_email'];
    $user_password = $_POST['password'];  
    try {
        $sth = $dbh->prepare("SELECT * FROM logindata WHERE email=:email");
        $sth->execute(array(":email"=>$user_email));
        $count = $sth->rowCount();   
        if($count==0){    
            $sth = $dbh->prepare("INSERT INTO logindata(username,email,pass) VALUES(:uname, :email, :pass)");
            $sth->bindParam(":uname",$user_name);
            $sth->bindParam(":email",$user_email);
            $sth->bindParam(":pass",$user_password);   
            if(!$sth->execute()) {
                echo "3";  
            } else {
                echo "2";
            }
        } else{    
        echo "1"; 
        }    
    }
    catch(PDOException $e){
        echo $e->getMessage();
    }
}
?>

使用PDO。

dbconnect.php：

<?php
  $dbhost='localhost';
  $dbuser='root';
  $dbpass='';
  $dbname='ambitio';  
  try{
    $dbh=new PDO("mysql:host={$dbhost};dbname={$dbname}",$dbuser,$dbpass);
    $dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
  }
  catch(PDOException $e){
    echo $e->getMessage();
  }  
?>

问题：这两个响应都没有被返回到jQuery ajax调用。我查看了console.log()，但浏览器中没有显示任何内容。数据存储在MySQL数据库中（检查它），这意味着execute()在PHP中工作正常，但浏览器中仍然没有显示警报。如果1评估为count，则会返回0。

此外，当我在没有实际提交表单的情况下刷新表单时，我在浏览器控制台上收到错误POST 412 (Precondition Failed)。

编辑：发布完整的php。

EDIT2：Apache访问日志

::1 - - [19/Jul/2016:23:51:55 +0530] "GET /ambitio/css/bootstrap.css HTTP/1.1" 304 - "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [19/Jul/2016:23:51:55 +0530] "GET /ambitio/css/overboot.css HTTP/1.1" 304 - "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [19/Jul/2016:23:51:55 +0530] "GET /ambitio/css/font-awesome.css HTTP/1.1" 304 - "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [19/Jul/2016:23:51:55 +0530] "GET /ambitio/js/jquery.js HTTP/1.1" 304 - "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [19/Jul/2016:23:51:55 +0530] "GET /ambitio/js/bootstrap.js HTTP/1.1" 304 - "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [20/Jul/2016:00:43:36 +0530] "GET /ambitio/signup.html HTTP/1.1" 200 1454 "-" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [20/Jul/2016:00:43:46 +0530] "POST /ambitio/signup.html HTTP/1.1" 200 1454 "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
::1 - - [20/Jul/2016:00:43:46 +0530] "POST /ambitio/signup.php HTTP/1.1" 200 1 "http://localhost/ambitio/signup.html" "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"

EDIT3：表单HTML标记：

<form method="post" id="regform" onSubmit="submitForm()">
      <input type="text" placeholder="Username" id="user_name" name="user_name" />
      <input type="email" placeholder="Email" id="user_email" name="user_email" />
      <input type="password" placeholder="Password" id="password" name="password" />
      <input type="password" placeholder="Retype password" id="rpassword" name="rpassword" />
      <input type="submit" id="submit"/>
</form>

Answer 1

由于您的表单不包含要发送的网址，而您的onSubmit - 处理程序（submitForm）没有返回false，表单实际上会获得由浏览器发布到它当前所在的页面（很可能无法处理表单的POST数据），只会重新加载包含页面的登录表单。

POST可能会发送到您的ajax脚本以及，但您的浏览器不会等待响应，因为它已经继续。

有关提交流程的详细信息，请参阅https://html.spec.whatwg.org/multipage/forms.html#concept-form-submit。

解决方案是将return false添加到submitForm函数或onSubmit处理程序（;return false）

PHP对AJAX请求没有响应

1 个答案: