提交表单时成功/错误消息不断消失

Question

我有一个应用程序(editsessionadmin.php)，用户在其中在相关文本输入中显示他们的评估名称、日期和时间。现在当用户提交时，它会显示一个确认，当用户确认时，然后通过使用ajax，它会导航到updatedatetime.php，它将在数据库中更新评估的时间和日期，并在editsessionadmin.php 页面的顶部。

但是我有一个小问题。

问题：使用 div 标记，我能够从 updatedatetime.php 脚本中检索更新后的错误或成功消息，并使用此 jquery 代码 $("#targetdiv").html(data) 在 editsessionadmin.php 脚本中显示它。问题是，当用户提交表单时，它会显示消息，然后在提交表单后消息消失。我希望消息显示在editsessionadmin.php 页面的顶部而不是消失。为什么会消失？

下面是editsessionadmin.php的代码

        <script>

    function submitform() {    

    $.ajax({
        type: "POST",
        url: "/updatedatetime.php",
        data: $('#updateForm').serialize(),
        success: function(html){
            $("#targetdiv").html(html);
        }
     });        
}

         function showConfirm(){

          var examInput = document.getElementById('newAssessment').value;
          var dateInput = document.getElementById('newDate').value;
          var timeInput = document.getElementById('newTime').value;

          if (editvalidation()) {

         var confirmMsg=confirm("Are you sure you want to update the following:" + "\n" + "Exam: " + examInput +  "\n" + "Date: " + dateInput + "\n" + "Time: " + timeInput);

         if (confirmMsg==true)
         {
         submitform();   
     }
  }
} 

$('body').on('click', '#updateSubmit', showConfirm); 

            </script>   

        <h1>EDIT AN ASSESSMENT'S DATE/START TIME</h1>   

        <p>You can edit assessment's Date and Start time on this page. Only active assessments can be editted.</p>

        <div id="targetdiv"></div>

        <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post" onsubmit="return validation();">
        <table>
        <tr>
        <th>Course: INFO101</th>
        <th>Module: CHI2513</th>
        </tr>
        </table>
        <p><input id="moduleSubmit" type="submit" value="Submit Course and Module" name="moduleSubmit" /></p>

        </form>


        ....


        <?php
        $editsession = "<form id='updateForm'>

        <p><strong>New Assessment's Date/Start Time:</strong></p>
        <table>
        <tr>
        <th>Assessment:</th>
        <td><input type='text' id='newAssessment' name='Assessmentnew' readonly='readonly' value='' /> </td>
        </tr>
        <tr>
        <th>Date:</th> 
        <td><input type='text' id='newDate' name='Datenew' readonly='readonly' value='' /> </td>
        </tr>
        <tr>
        <th>Start Time:</th> 
        <td><input type='text' id='newTime' name='Timenew' readonly='readonly' value=''/><span class='timepicker_button_trigger'><img src='Images/clock.gif' alt='Choose Time' /></span> </td>
        </tr>
        </table>
        <div id='datetimeAlert'></div>

<button id='updateSubmit'>Update Date/Start Time</button>


        </form>
        ";

        echo $editsession;


        }

        ?>

下面是updatedatetime.php的代码：

<?php

 // connect to the database
 include('connect.php');

  /* check connection */
  if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    die();
  }

echo 'sumbit successful';

$sessionname = (isset($_POST['Assessmentnew'])) ? $_POST['Assessmentnew'] : ''; 
$sessiondate = (isset($_POST['Datenew'])) ? $_POST['Datenew'] : ''; 
$sessiontime = (isset($_POST['Timenew'])) ? $_POST['Timenew'] : ''; 

$formatdate = date("Y-m-d",strtotime($sessiondate));
$formattime = date("H:i:s",strtotime($sessiontime));

$updatesql = "UPDATE Session SET SessionDate = ?, SessionTime = ? WHERE SessionName = ?";                                           
$update = $mysqli->prepare($updatesql);
$update->bind_param("sss", $formatdate, $formattime, $sessionname);
$update->execute();

echo 'update successful';

$query = "SELECT SessionName, SessionDate, SessionTime FROM Session WHERE SessionName = ?";
// prepare query
$stmt=$mysqli->prepare($query);
// You only need to call bind_param once
$stmt->bind_param("s", $sessionname);
// execute query
$stmt->execute(); 
// get result and assign variables (prefix with db)
$stmt->bind_result($dbSessionName, $dbSessionDate, $dbSessionTime);
//get number of rows
$stmt->store_result();
$numrows = $stmt->num_rows();

echo 'select successful';

if ($numrows == 1){

echo "<span style='color: green'>Your Assessment's new Date and Time have been updated</span>";

}else{

echo "<span style='color: red'>An error has occured, your Assessment's new Date and Time have not been updated</span>";

}

        ?>

Answer 1

好的，清理代码，执行表单提交，这就是 ajax 调用所需要的全部

function submitupdate() {    

    $.ajax({
        type: "POST",
        url: "/updatedatetime.php",
        data: $('#updateForm').serialize(),
        success: function(html){
            $("#targetdiv").html(html);
        }
     });        
}

这假设

/updatedatetime.php

正确计算并回显更新的成功或失败，

这是一个FIDDLE，向您展示表单本身所需的最低要求。您不需要在表单本身上放置任何方法或操作，只需表单标签即可。

至于提交按钮...你可以把它放在任何地方，做任何事情，只要确保你给它一个 ID 并附加一个点击处理程序来提交表单。

Answer 2

您必须在 post call 中删除再次提交表单的行，并且该行恰好是 updateFormO.submit(); 。使用 post 方法进行 ajax 调用，然后在成功函数中再次重新提交表单。