開通微信開發者模式

1、註冊微信公衆平臺；

2、用百度或者新浪開發引擎作爲自己的服務器；

<?php
/**
  * wechat php test
  */

//define your token
define("TOKEN", "wechatnow");//這裏填寫自己的token
$wechatObj = new wechatCallbackapiTest();
$wechatObj->valid();

class wechatCallbackapiTest
{
	public function valid()
    {
        $echoStr = $_GET["echostr"];

        //valid signature , option
        if($this->checkSignature()){
        	echo $echoStr;
        	exit;
        }
    }

    public function responseMsg()
    {
		//get post data, May be due to the different environments
		$postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

      	//extract post data
		if (!empty($postStr)){
                
              	$postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
                $fromUsername = $postObj->FromUserName;
                $toUsername = $postObj->ToUserName;
                $keyword = trim($postObj->Content);
                $time = time();
                $textTpl = "<xml>
		<ToUserName><![CDATA[%s]]></ToUserName>
		<FromUserName><![CDATA[%s]]></FromUserName>
		<CreateTime>%s</CreateTime>
		<MsgType><![CDATA[%s]]></MsgType>
		<Content><![CDATA[%s]]></Content>
		<FuncFlag>0</FuncFlag>
		</xml>";             
	       if(!empty( $keyword ))
                {
              		$msgType = "text";
                	$contentStr = "Welcome to wechat world!";
                	$resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
                	echo $resultStr;
                }else{
                	echo "Input something...";
                }

        }else {
        	echo "";
        	exit;
        }
    }
		
	private function checkSignature()
	{
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];	
        		
		$token = TOKEN;
		$tmpArr = array($token, $timestamp, $nonce);
		sort($tmpArr);
		$tmpStr = implode( $tmpArr );
		$tmpStr = sha1( $tmpStr );
		
		if( $tmpStr == $signature ){
			return true;
		}else{
			return false;
		}
	}
}

?>

 最後很多人都不知道怎樣填寫url，url應該是網址加上文件名，比如http://######.com/index.php，這樣就ok！