<"TOKEN", "weixin");
$wechatObj = new wechatCallbackapiTest();
//$wechatObj->valid();
$wechatObj->responseMsg();
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 ))
    {
     $msgType = "text";
     if($keyword=="1"){
     $contentStr = "qiphon";}
     if($keyword=="2"){
     $contentStr = "最新资讯：《环境违法行为举报奖励办法》";}
     if($keyword=="3"){
     $contentStr = "31离婚协议\n32租房合同\n33交通事故协议书";}     
     $resultStr = sprintf($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;
  }
 }
}

?>