php - 使用AJAX将查询发送到php文件时，变量保持为空

Question

我有一个表单，在提交表单之前我会进行一些AJAX错误处理，只是为了改善用户体验。我的问题是变量$user_password在整个过程中似乎都为空，因此错误处理是无关紧要的。

在以下代码中，第一个键入功能用于检查密码是否长于最小长度，第二个用于检查密码是否匹配:

$(document).ready(function() {
    $("input[name=user_password]").keyup(function(){    
        var user_password = $("input[name=user_password]").val();
        //data to server...
        $.post("../server/hub.php", {
            //POST name and variable... 
            check_password: user_password
            //places fetched information...
        }, function(data, status) {
            $("#user_password").html(data);
        });
    });
});


$(document).ready(function() {

    $("input[name=user_password_2]").keyup(function(){
        var user_password = $("input[name=user_password]").val();
        var user_password_2 = $("input[name=user_password_2]").val();
        //data to server...
        $.post("../server/hub.php", {
            //POST name and variable... 
            password_match: user_password,
            password_match_2: user_password_2
            //places fetched information...
        }, function(data, status) {
            $("#user_password_2").html(data);
        });
    });

});

变量被重定向到实际执行错误处理的php文件:

if (isset($_POST['check_password'])) {
    $user_password = $_POST['check_password'];

    echo $user_password;

    if ($user_password == "") {
        echo "";
    } elseif (strlen($user_password) < 6) {
        echo "Password must contain at least six characters!";
    } else {
        echo "You are good to go!";
    }
}

if (isset($_POST['password_match'])) {
    $user_password = $_POST['password_match'];
    $user_password_2 = $_POST['password_match_2'];

    if ($user_password_2 == "") {
        echo "";
    } elseif ($user_password !== $user_password_2) {
        echo "Sorry, passwords do not match!";
    } else {
        echo "You are good to go!";
    }
}

尽管返回到html文件的数据仍然为空，并且回显 $user_password不会产生任何结果。

这是html段:

<form action="../server/register.php" method="POST">
                        <div class="input_table">                           
                            <table>
                                <thead>
                                    <tr>
                                        <th><h1>Register to LIMS</h1></th>
                                    </tr>
                                </thead>
                                <tbody>

                                    <tr>
                                        <td><input type="password" name="user_password" placeholder="Select Password"><p id="user_password"></p></td>
                                    </tr>
                                    <tr>
                                        <td><input type="password" name="user_password_2" placeholder="Repeat Password"><p id="user_password_2"></p></td>
                                    </tr>
                                </tbody>
                            </table>
                        </div>
                        <button type="submit" name="user_register" class="button_1">Register</button>
                        <button type="button" class="button_3">Cancel</button>              
                    </form>

谁能解释为什么会这样？

Answer 1

当您编写代码时，我能够使您的代码正常工作。

我为html创建了一个空白页test.php:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<form action="../server/register.php" method="POST">

  <div class="input_table">
    <table>
      <thead>
        <tr>
          <th><h1>Register to LIMS</h1></th>
        </tr>
        </thead>
        <tbody>
          <tr>
            <td><input type="password" name="user_password" placeholder="Select Password"><p id="user_password"></p></td>
          </tr>
          <tr>
            <td><input type="password" name="user_password_2" placeholder="Repeat Password"><p id="user_password_2"></p></td>
          </tr>
        </tbody>
    </table>
  </div>

  <button type="submit" name="user_register" class="button_1">Register</button>
  <button type="button" class="button_3">Cancel</button>

</form>

<script>

$(document).ready(function() {
  $("input[name=user_password]").keyup(function(){
      var user_password = $("input[name=user_password]").val();
      //console.log('password 1 key up'); //Check for key up.. It works
      //data to server...
      $.post("hub.php", {
          //POST name and variable...
          check_password: user_password
          //places fetched information...
      }, function(data, status) {
          console.log(data); //Check for your data.
          $("#user_password").html(data); //Data was displayed in div.
      });
  });
});


$(document).ready(function() {

  $("input[name=user_password_2]").keyup(function(){
      var user_password = $("input[name=user_password]").val();
      var user_password_2 = $("input[name=user_password_2]").val();
      //data to server...
      $.post("hub.php", {
          //POST name and variable...
          password_match: user_password,
          password_match_2: user_password_2
          //places fetched information...
      }, function(data, status) {
          $("#user_password_2").html(data);
      });
  });

});

</script>

注意，我使用 hub.php作为AJAX的URL。

另一件事是我正在使用Jquery 3.1.1，并且在表单之前加载了库。

我还将您的jquery代码包装在 <script>标记中。

我将 hub.php页面与 test.php放在同一文件夹中:

<?php

echo 'I made it.';  //Test to see if you landed on the page.

if (isset($_POST['check_password'])) {
    $user_password = $_POST['check_password'];

    echo $user_password;

    if ($user_password == "") {
        echo "";
    } elseif (strlen($user_password) < 6) {
        echo "Password must contain at least six characters!";
    } else {
        echo "You are good to go!";
    }
}

if (isset($_POST['password_match'])) {
    $user_password = $_POST['password_match'];
    $user_password_2 = $_POST['password_match_2'];

    if ($user_password_2 == "") {
        echo "";
    } elseif ($user_password !== $user_password_2) {
        echo "Sorry, passwords do not match!";
    } else {
        echo "You are good to go!";
    }
}


?>

我绝对会检查您的路径。如果您在控制台中没有看到响应，则说明您未将AJAX定向到正确的目录。

我对此进行了测试，并且可以正常工作。