PHP表單，如何在同一頁面上回顯？

Question

確定這裏是情況，我想使用登錄表單

<form name="form1" method="post" action="sign.php"> 
    Username:<br/> 
    <input name="myusername" type="text" id="myusername" /><br /> 
    Password:<br /> 
    <input name="mypassword" type="text" id="mypassword" /><br /> 
    <input type="submit" name="Submit" value="Login" /> 
</form> 

sign.php

<?php 
ob_start(); 
$host="localhost"; // Host name 
$username="root"; // Mysql username 
$password=""; // Mysql password 
$db_name="cosmos"; // Database name 
$tbl_name="members"; // Table name 

// Connect to server and select databse. 
mysql_connect("$host", "$username", "$password")or die("cannot connect"); 
mysql_select_db("$db_name")or die("cannot select DB"); 

// Define $myusername and $mypassword 
$myusername=$_POST['myusername']; 
$mypassword=$_POST['mypassword']; 

// To protect MySQL injection (more detail about MySQL injection) 
$myusername = stripslashes($myusername); 
$mypassword = stripslashes($mypassword); 
$myusername = mysql_real_escape_string($myusername); 
$mypassword = mysql_real_escape_string($mypassword); 
$mypassword = md5($mypassword); 

$sql="SELECT * FROM $tbl_name WHERE username='$myusername' and password='$mypassword'"; 
$result=mysql_query($sql); 

// Mysql_num_row is counting table row 
$count=mysql_num_rows($result); 
// If result matched $myusername and $mypassword, table row must be 1 row 

if($count==1){ 
// Register $myusername, $mypassword and redirect to file "login_success.php" 
session_register("myusername"); 
session_register("mypassword"); 
header("location:login_success.php"); 
} 
else { 
echo "Wrong Username or Password"; 
} 

    ob_end_flush(); 
?> 

在情況下，如果用戶輸入錯誤的詳細信息，然後我想這顯示等形式的東西一樣......「錯誤的用戶名或密碼的同一頁上，請再試一次......「，我們在底部形成

Answer 1

測試以查看POST是否發生。如果是這樣，那麼驗證憑證;如果正確，則重定向到目標頁面;如果不正確，則顯示錯誤消息。然後輸出表單。