網站構建三（身份驗證）

使用PHP和MySQL實現了用戶的用戶的身份驗證。

用戶登錄，實現用戶輸入與MySQL數據的匹配：

<?php
	$name=$_POST['username'];
	$password=$_POST['password'];
	
	if((!isset($name))||(!isset($password))){
		require("login.php");
	}
	else{
		$mysql=mysqli_connect("localhost","webauth","webauth");
		if(!$mysql){
			echo "Cannot connect to database.";
			exit;
		}
		
		$selected=mysqli_select_db($mysql,"auth");
		if(!$selected){
			echo "Cannot select database.";
			exit;
		}
		
		$query='select count(*) from authorized_users where
				usernamesignup="'.$name.'"and 
				passwordsignup="'.$password.'"';
		
		$result=mysqli_query($mysql,$query);
		if(!$result){
			echo "Cannot run query.";
			exit;
		}
		
		$row=mysqli_fetch_row($result);
		$count=$row[0];
		
		if($count>0){
			require("home.php");
		}
		else{
			echo "<h1>Go Away!</h1>
				  <p>You are not authorized to use this resourse.</p>";
		}
	}
?>

用戶註冊，實現數據插入存儲：

<?php
	$usernamesignup=$_POST['usernamesignup'];
	$emailsignup=$_POST['emailsignup'];
	$passwordsignup=$_POST['passwordsignup'];
	$passwordsignup_confirm=$_POST['passwordsignup_confirm'];
	
	if(!get_magic_quotes_gpc()){
		$usernamesignup=addslashes($usernamesignup);
		$emailsignup=addslashes($emailsignup);
		$passwordsignup=addslashes($passwordsignup);
		$passwordsignup_confirm=addslashes($passwordsignup_confirm);
	}
	
	if($passwordsignup==$passwordsignup_confirm){
		@$db=mysqli_connect("localhost","webauth","webauth");	
		if(!$db){
			echo "Error:Could not connect to database.Please try again later.";
			exit;
		}
	
		$selected=mysqli_select_db($db,"auth");
		if(!$selected){
				echo "Cannot select database.";
				exit;
			}
		$query="insert into authorized_users values
				('".$usernamesignup."','".$emailsignup."','".$passwordsignup."','".$passwordsignup_confirm."')";
		$result=mysqli_query($db,$query);
	
		if($result){
			echo "user inserted into database.";
		}
		else{
			echo "An error has occurred.The item was not added.";
		}
	
		$db->close();
	}
	else{
		echo "Password doesn't match.Please enter the same values.";
		exit;
	}
?>
	
	

待解決問題：如果同一個用戶，多次註冊，應該有對策。登陸後的相關頁面顯示也有待改進。