PHP的一个日志记录工具类

接入微信支付SDK的时候，在提供的DEMO里面发现了一个这个log日志的工具类，感觉还挺方便的，所以拿来稍微修改了一下，用在一些小的php项目中还是很好用的。
完整的log.php文件:<?php
//设置时区
ini_set('date.timezone','Asia/Shanghai');
//以下为日志

interface ILogHandler
{
public function write($msg);
}

class CLogFileHandler implements ILogHandler
{
private $handle = null;

public function __construct($file = '')
{
$this->handle = fopen($file,'a');
}

public function write($msg)
{
fwrite($this->handle, $msg, 4096);
}

public function __destruct()
{
fclose($this->handle);
}
}

class Log
{
private $handler = null;
private $level = 15;

private static $instance = null;

private function __construct(){}

private function __clone(){}

public static function Init($handler = null,$level = 15)
{
if(!self::$instance instanceof self)
{
self::$instance = new self();
self::$instance->__setHandle($handler);
self::$instance->__setLevel($level);
}
return self::$instance;
}

private function __setHandle($handler){
$this->handler = $handler;
}

private function __setLevel($level)
{
$this->level = $level;
}

public static function DEBUG($msg)
{
self::$instance->write(1, $msg);
}

public static function WARN($msg)
{
self::$instance->write(4, $msg);
}

public static function ERROR($msg)
{
$debugInfo = debug_backtrace();
$stack = "[";
foreach($debugInfo as $key => $val){
if(array_key_exists("file", $val)){
$stack .= ",file:" . $val["file"];
}
if(array_key_exists("line", $val)){
$stack .= ",line:" . $val["line"];
}
if(array_key_exists("function", $val)){
$stack .= ",function:" . $val["function"];
}
}
$stack .= "]";
self::$instance->write(8, $stack . $msg);
}

public static function INFO($msg)
{
self::$instance->write(2, $msg);
}

private function getLevelStr($level)
{
switch ($level)
{
case 1:
return 'debug';
break;
case 2:
return 'info';
break;
case 4:
return 'warn';
break;
case 8:
return 'error';
break;
default:

}
}

protected function write($level,$msg)
{
if(($level & $this->level) == $level )
{
$msg = '['.date('Y-m-d H:i:s').']['.$this->getLevelStr($level).'] '.$msg."\n";
$this->handler->write($msg);
}
}
}

使用方法:
1.包含log.php文件:require_once "log.php";2.初始化日志文件:$logHandler= new CLogFileHandler("logs/".date('Y-m-d').'.log');
$log = Log::Init($logHandler, 15);
其中CLogFileHandler的参数为日志文件的存放路径，这里需要我们手动创建logs文件夹并给予权限。
然后就可以输出日志了：Log::DEBUG("DEBUG");
Log::WARN("WARN");
Log::ERROR("ERROR");
Log::INFO("INFO");这里我们分别输出了4种日志内容
运行我们的测试脚本，就可以看到logs文件夹中已经生成了日志文件。
查看日志文件就可以看到我们输出的日志内容了：