<form action="verify.PHP" method="post">
User Name:<br>
<input type="text" name="username"><br><br>
Password:<br>
<input type="password" name="password"><br><br>
<input type="submit" name="submit" value="Login">
</form>

<!--   来自 编程之家 jb51.cc （jb51.cc）-->

/**
 * 
 *
 * @param 
 * @author 编程之家 jb51.cc jb51.cc
 **/
if(isset($_POST['submit'])){ 
$dbHost = "localhost"; //Location Of Database usually its localhost 
$dbUser = "xxxx"; //Database User Name 
$dbPass = "xxxxxx"; //Database Password 
$dbDatabase = "db_name"; //Database Name 

$db = MysqL_connect($dbHost,$dbUser,$dbPass)or die("Error connecting to database."); 
//Connect to the databasse 
MysqL_select_db($dbDatabase,$db)or die("Couldn't select the database."); 
//Selects the database 

/* 
The Above code can be in a different file,then you can place include'filename.PHP'; instead. 
*/ 

//Lets search the databse for the user name and password 
//Choose some sort of password encryption,I choose sha256 
//Password function (Not In all versions of MysqL). 
$usr = MysqL_real_escape_string($_POST['username']); 
$pas = hash('sha256',MysqL_real_escape_string($_POST['password'])); 
$sql = MysqL_query("SELECT * FROM users_table 
WHERE username='$usr' AND 
password='$pas' 
LIMIT 1"); 
if(MysqL_num_rows($sql) == 1){ 
$row = MysqL_fetch_array($sql); 
session_start(); 
$_SESSION['username'] = $row['username']; 
$_SESSION['fname'] = $row['first_name']; 
$_SESSION['lname'] = $row['last_name']; 
$_SESSION['logged'] = TRUE; 
header("Location: users_page.PHP"); // Modify to go to the page you would like 
exit; 
}else{ 
header("Location: login_page.PHP"); 
exit; 
} 
}else{ //If the form button wasn't submitted go to the index page,or login page 
header("Location: index.PHP"); 
exit; 
} 

/**
 * 
 *
 * @param 
 * @author 编程之家 jb51.cc jb51.cc
 **/
session_start(); 
if(!$_SESSION['logged']){ 
header("Location: login_page.PHP"); 
exit; 
} 
echo 'Welcome,'.$_SESSION['username']; 



/***   代码来自编程之家 jb51.cc（jb51.cc）   ***/