Question

下面是我使用Ajax从数据库检查用户名的代码。来自html页面的输入文本不会转到checkusername.php $_POST['uname'];可能是什么错误？我尝试了一切仍然无法正常工作。当点击按钮时，用户名文本框中的值如何被带入checkusername.php文件？

html页面代码

<input type="text" name="uname" class="form-control" id="username" placeholder="UserName (0-9,A-Z,a-z)">
<input type='button' id='check_username_availability' value='Check Username Availability'>
  <div id='username_availability_result'></div>

checkusername.php

<?php

   $con=mysqli_connect("localhost","root","","database")or die(mysqli_error());

   //get the username
      $username = mysqli_real_escape_string($con,$_POST['uname']);

       //mysql query to select field username if it's equal to the username that we check '
          $result =mysqli_query($con,"Select username from users where username='$username'") or die(mysqli_error($con));


      //if number of rows fields is bigger them 0 that means it's NOT available '
       if(mysqli_num_rows($result)>0){
     //and we send 0 to the ajax request
    echo 0;
    }else{
    //else if it's not bigger then 0, then it's available '
    //and we send 1 to the ajax request
    echo 1;
     }


        ?>

//用于检查实时用户名可用性的脚本

   <script>



 $(document).ready(function() {

    //the min chars for username
    var min_chars = 6;

     //result texts
    var characters_error ='Minimum amount of chars is 6';
     var checking_html = 'Checking...';

    //when button is clicked
     $('#check_username_availability').click(function(){
         //run the character number check
         if($('#username').val().length < min_chars){
             //if it's bellow the minimum show characters_error text '
            $('#username_availability_result').html(characters_error);
         }else{
             //else show the cheking_text and run the function to check
             //$('#username_availability_result').html(checking_html);
             check_availability();
            }
        });

         });

    //function to check username availability
     function check_availability(){

    //get the username
    var username = $('#username').val();

    //use ajax to run the check
    $.post("checkusername.php",{ username: uname },
        function(result){
            //if the result is 1
            if(result == 1){
                //show that the username is available
                $('#username_availability_result').html(username + ' is Available');
            }else{
                //show that the username is NOT available
                $('#username_availability_result').html(username + ' is not Available');
            }
          });

    }




    </script>

Answer 1

交换价值：

{ username: uname }

到此：

{ uname: username }

因为当你发送uname时，php正在期待一个名为$_POST['uname']的变量username。
因此，简单的改变是交换对象中的属性。

Answer 2

简单的拼写错误。

更改

var username = $('#username').val();
//use ajax to run the check
$.post("checkusername.php",{ username: uname },

要

var username = $('#username').val();
//use ajax to run the check
$.post("checkusername.php",{ uname: username },// Observe username.

Answer 3

您要发布到checkusername.php {username: uname} 并尝试获取$_POST['uname']和js中没有uname变量。将{ username: uname }更改为{ uname: username }

这个ajax代码里面的错误是什么？

3 个答案: