定义$message＝“"；变量 - definining $message="" variable

definining $message="" variable

本文关键字：quot 变量 message 定义 | 更新日期: 2023-10-28

这段代码运行良好，只是我收到了一个未定义的变量警告"message"，并且我无法找到定义它的方法，因为它不是post或session变量或其他任何东西。感谢

<?php
if (isset($_POST['submit']))
{
  $newemail = $_POST['newemail'];
  $repeatnewemail = $_POST['repeatnewemail'];
  $email= ($_SESSION['email']);
  $message="";
 //open database
  if (condition)
  {
    $message="first message";
  }
}
?>
<p td class='td2'><?php echo $message;?></td>

将$message="";置于条件之外。

$message="";
if (isset($_POST['submit'])){
    $newemail = $_POST['newemail'];
    $repeatnewemail = $_POST['repeatnewemail'];
    $email= ($_SESSION['email']);

 //open database

    if (condition){
        $message="first message";
    }
}
?>
<p td class='td2'><?php echo $message;?></td>

在顶部声明$message：-

$message = ""
if (isset($_POST['submit']))
{
 $newemail = $_POST['newemail'];
 $repeatnewemail = $_POST['repeatnewemail'];
 $email= ($_SESSION['email']);
 //open database

 if (condition)
 {
  $message="first message";
 }
}
?>
 <p td class='td2'><?php if(isset($message)) echo $message;?></td>

$message=null;
if (isset($_POST['submit']))
{
 $newemail = $_POST['newemail'];
 $repeatnewemail = $_POST['repeatnewemail'];
 $email= ($_SESSION['email']);
 $message="";
 //open database

 if (condition)
 {
  $message="first message";
 }
}
?>
 <p td class='td2'><?php if(isset($message)) echo $message;?></td>

您得到的错误是因为您没有定义$message。

$message = ""
if (isset($_POST['submit']))
{
 $newemail = $_POST['newemail'];
 $repeatnewemail = $_POST['repeatnewemail'];
 $email= ($_SESSION['email']);
 //open database

 if (condition)
 {
  $message="first message";
 }
}
?>
 <p td class='td2'><?php if(isset($message)) echo $message;?></td>

将$message=""置于if (isset($_POST['submit'])) { }块之前