php - 重新加载后页面变成空白

Question

无法理解重新加载成员(member)页面(登录后)后页面变成空白。但所有其他事情都工作正常。

下面是登录表单页面后login_execution.php页面的代码

<?php

session_start();
$con=mysql_connect("localhost","root","");
if (!$con) {
    die('Could not connect: ' . mysql_error());
}
$db_selected = mysql_select_db('loged', $con);
if(isset($_POST["submit"])) {
$username=mysql_real_escape_string($_POST['username']); 
$password=mysql_real_escape_string($_POST['password']); 
$password=md5($password); 
 $sql="SELECT username FROM  list WHERE username='$username' and password='$password'";
$result=mysql_query($sql);
$count=mysql_num_rows($result);


if($count==1)
{
session_regenerate_id();
    $_SESSION['username'] = $username;
    $_SESSION['password'] = $password;
    session_write_close();
    echo "<table>
<tr>
<th>username</th>";



     $row = mysql_fetch_array($result) 

    ?>
  <tr style="background-color:blue;color:white;"> 
          <td><font size="6"><?php echo $row['username']; ?></font></td>
          <h1 align="center"><font size="6" color="blue">welcome <?php echo $row['username']; ?></font></h1>
          <p align="right"><font size="4" color="#380B61"><a href="logout.php">Logout</a></font></td>





        </tr>
          <?php


echo "</table>";
}

else 
{
?> 
<h1 align="center"><font size="4" color="red">enter coerrect username and password</font></h1>
<td><a href="login.php">BACK</a></td>
<?php
}
}
?>

Answer 1

您的条件是，如果在重新加载页面时单击提交，则不会单击提交按钮，因此不会显示任何内容。

要纠正此问题，请使用以下代码。

<?php

session_start();
$con=mysql_connect("localhost","root","");
if (!$con) {
    die('Could not connect: ' . mysql_error());
}
$db_selected = mysql_select_db('loged', $con);
if(isset($_POST["submit"])) {
$username=mysql_real_escape_string($_POST['username']); 
$password=mysql_real_escape_string($_POST['password']); 
$password=md5($password); 
 $sql="SELECT username FROM  list WHERE username='$username' and password='$password'";
$result=mysql_query($sql);
$count=mysql_num_rows($result);

if($count==1)
{
$row = mysql_fetch_array($result)
session_regenerate_id();
    $_SESSION['username'] = $username;
    $_SESSION['password'] = $password;
    $_SESSION['name'] = $row['username'];
    session_write_close();
}
}


if(isset($_SESSION['username']))
{
   echo "<table>
<tr>
<th>username</th>";





    ?>
  <tr style="background-color:blue;color:white;"> 
          <td><font size="6"><?php echo $row['username']; ?></font></td>
          <h1 align="center"><font size="6" color="blue">welcome <?php echo $_SESSION['name']; ?></font></h1>
          <p align="right"><font size="4" color="#380B61"><a href="logout.php">Logout</a></font></td>





        </tr>
          <?php


echo "</table>";
}

else 
{
?> 
<h1 align="center"><font size="4" color="red">enter coerrect username and password</font></h1>
<td><a href="login.php">BACK</a></td>
<?php
}
?>