微信开发一【启用公众平台服务器配置】

<?php
/**
  * 微信主页【关注回复】
  */

class Wechat_Sign
{
    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)){
                /* libxml_disable_entity_loader is to prevent XML eXternal Entity Injection,
                   the best way is to check the validity of xml by yourself */
                libxml_disable_entity_loader(true);
                  $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
                $fromUsername = $postObj->FromUserName;
                $toUsername = $postObj->ToUserName;
                $keyword = trim($postObj->Content);
                $eventkey = trim($postObj->EventKey);
                $event = $postObj->Event;
                $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>';  

                //关注回复
                if ($event == "subscribe"){
                    $msgType = "text";
                    $contentStr = 'hi，欢迎您关注四川现代服务号，小编已经等您很久了，为了更好地给您服务，请先绑定四川现代账户 '.' <a href="http://www.baidu.com">账号绑定</a>';
                    $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
                    echo $resultStr;
                }
                
                //对话回复
//                 if(!empty( $keyword ))
//                 {
//                     $msgType = "text";
//                     $contentStr = 'hi，欢迎您关注四川现代服务号，小编已经等您很久了，为了更好地给您服务，请先绑定四川现代账户 '.'<a href="http://www.baidu.com">账号绑定</a>';
//                     $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
//                     echo $resultStr;
//                 }else{
//                     echo "Input something...";
//                 }

        }else {
            echo "";
            exit;
        }
    }

    /**
     * 验证微信
     * @throws Exception
     * @return boolean
     */
    private function checkSignature()
    {
        // you must define TOKEN by yourself
        if (!defined("TOKEN")) {
            throw new Exception('TOKEN is not defined!');
        }
        
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];
                
        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        // use SORT_STRING rule
        sort($tmpArr, SORT_STRING);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );
        
        if( $tmpStr == $signature ){
            return true;
        }else{
            return false;
        }
    }
}

/**
*调用
*/
/**
     *首页【验证】
     */
    public function index()
    {
        define("TOKEN", "XXXXXXXX");
        $wechatObj = new Wechat_Sign();
        if (isset($_GET['echostr'])) {
            $wechatObj->valid();
        } else {
            $wechatObj->responseMsg();
        }
        
    }
?>