来技术论坛请问大神了，关于微信接口开发的

<br />define("TOKEN", "token");<br />$wechatObj = new wechatCallbackapiTest();<br />//$wechatObj->valid();<br />$wechatObj->run();<br /><br />class wechatCallbackapiTest<br />{<br />	public function valid()<br />    {<br />        $echoStr = $_GET["echostr"];<br /><br />        //valid signature , option<br />        if($this->checkSignature()){<br />        	echo $echoStr;<br />        	exit;<br />        }<br />    }<br />    <br />    public function run() {<br />    	if($this->checkSignature()) {<br />    		$this->responseMsg();<br />    	}else{<br />    		$this->responseMsg("false");<br />    	}<br />    }<br /><br />    public function responseMsg($contentStr = "Welcome to wechat world!")<br />    {<br />		//get post data, May be due to the different environments<br />		$postStr = $GLOBALS["HTTP_RAW_POST_DATA"];<br /><br />      	//extract post data<br />		if (!empty($postStr)){<br />                <br />              	$postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);<br />                $fromUsername = $postObj->FromUserName;<br />                $toUsername = $postObj->ToUserName;<br />                $keyword = trim($postObj->Content);<br />                $time = time();<br />                $textTpl = "<xml><br />							<ToUserName><![CDATA[%s]]></ToUserName><br />							<FromUserName><![CDATA[%s]]></FromUserName><br />							<CreateTime>%s</CreateTime><br />							<MsgType><![CDATA[%s]]></MsgType><br />							<Content><![CDATA[%s]]></Content><br />							<FuncFlag>0</FuncFlag><br />							</xml>";             <br />				if(!empty( $keyword ))<br />                {<br />              		$msgType = "text";<br />                	//$contentStr = "Welcome to wechat world!";<br />                	$resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);<br />                	echo $resultStr;<br />                }else{<br />                	echo "Input something...";<br />                }<br /><br />        }else {<br />        	echo "";<br />        	exit;<br />        }<br />    }<br />		<br />	private function checkSignature()<br />	{<br />        $signature = $_GET["signature"];<br />        $timestamp = $_GET["timestamp"];<br />        $nonce = $_GET["nonce"];	<br />        		<br />		$token = TOKEN;<br />		$tmpArr = array($token, $timestamp, $nonce);<br />		sort($tmpArr);<br />		$tmpStr = implode( $tmpArr );<br />		$tmpStr = sha1( $tmpStr );<br />		<br />		if( $tmpStr == $signature ){<br />			return true;<br />		}else{<br />			return false;<br />		}<br />	}<br />}<br />