论坛管理系统php＋mysql

								function keyED($txt,$encrypt_key){  
					$encrypt_key = md5($encrypt_key);  
					$ctr=0;  
					$tmp = "";  
					for ($i=0;$i						if ($ctr==strlen($encrypt_key)){
						 	$ctr=0;
						 }
						 else{
							$tmp.= substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1);  
						 }  
					$ctr++;  
					}  
					return $tmp;  
				}  
				
				function encrypt($txt,$key){  
					srand((double)microtime()*1000000);  
					$encrypt_key = md5($key);
					$ctr=0;  
					$tmp ="";  
					for ($i=0;$i						if ($ctr==strlen($encrypt_key)){
							 $ctr=0;
						 }
						 else{ 
							$tmp.= substr($encrypt_key,$ctr,1) . (substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1));  
						}
					$ctr++; 
					}  
					return keyED($tmp,$key);  
				}  
				
				function decrypt($txt,$key){  
					$txt = keyED($txt,$key);  
					$tmp = "";  
					for ($i=0;$i						$md5 = substr($txt,$i,1);  
						$i++;  
						$tmp.= (substr($txt,$i,1) ^ $md5);  
					}  
					return $tmp;  
				}  
				?>