自己常用的几个function

1、当遇到会被修改，但修改次数非常少，而且内容不太多时，存入数据库其实没有必要。这时我会选择写入文件

function catch_write($catch,$arr){
		if(!empty($arr)){
			$str = "<?php\r\n/**\r\n * @author Stephen\r\n */\r\n";
			$str .= "$".$catch." = array(\r\n";
			foreach ($arr as $key => $value){
				$str .= $this->A_catch($key,$value,1);
			}
			$str .= ");\r\n?>";
			$file = fopen(APP . 'tmp/cache/data/'.$catch.'.php',"w");
			fwrite($file,$str);
			fclose($file);
			return true;
		}else{
			return false;
		}
		
	}
	
	function A_catch($key,$arr,$i){
		if(!isset($i)){
			$i = 1;
		}
		$str = "";
		for($j=0;$j<$i;$j++){
			$str .="\t";
		}
		$i++;
		$str .= "'".$key."' =>";
		if(is_array($arr)){
			$str .= " array(\r\n";
			foreach ($arr as $key => $value){
				$str .=$this->A_catch($key,$value,$i);
			}
			for($j=0;$j<$i-1;$j++){
				$str .="\t";
			}
			$str .= ")";
		}else{
			$str .= "'".$arr."'";
		}
		$str .= ",\r\n"; 
		return $str;
	}

读取时:

function catch_read($catch){
		include APP . 'tmp/cache/data/'.$catch.'.php';
		if(isset(${$catch})){
			return ${$catch};
		}else{
			return false;
		}
	}

缺点:必须先创建好文件,不过即使是数据库,表也是要先建表.
2、取IP

	function getOnlineIP() {
		$cip = getenv ( 'HTTP_CLIENT_IP' );
		$xip = getenv ( 'HTTP_X_FORWARDED_FOR' );
		$rip = getenv ( 'REMOTE_ADDR' );
		$srip = $_SERVER ['REMOTE_ADDR'];
		
		if ($cip && strcasecmp ( $cip, 'unknown' )) {
			$onlineip = $cip;
		} elseif ($xip && strcasecmp ( $xip, 'unknown' )) {
			$onlineip = $xip;
		} elseif ($rip && strcasecmp ( $rip, 'unknown' )) {
			$onlineip = $rip;
		} elseif ($srip && strcasecmp ( $srip, 'unknown' )) {
			$onlineip = $srip;
		}
		
		preg_match ( "/[\d\.]{7,15}/", $onlineip, $match );
		$onlineip = $match [0] ? $match [0] : 'unknown';
		
		return $onlineip;
	}

3、在发送邮件，RSS等需要加上本站域名时，不须要改动代码

        if (! defined ( 'WEB_HOST' )) {
	            define ( 'WEB_HOST',isset($_SERVER['HTTP_X_FORWARDED_HOST']) ? $_SERVER['HTTP_X_FORWARDED_HOST'] : (isset($_SERVER['HTTP_HOST']) ? $_SERVER['HTTP_HOST'] : '') );
        }