Wechat official account server configuration

Using the method provided by wechat official service, errors have been reported all the time

{errcode: -106, errmsg: "token check fail"}
errcode: -106
errmsg: "token check fail"

  Then I found a solution on the Internet

        define("TOKEN", " It is set in the red box in the picture below token value ");
        $echostr = $_GET["echostr"];
        function checkSignature()
        {
            $signature = $_GET["signature"];
            $timestamp = $_GET["timestamp"];
            $nonce = $_GET["nonce"];

            $token = TOKEN;
            $tmpArr = array($token, $timestamp, $nonce);
            sort($tmpArr, SORT_STRING);
            $tmpStr = implode( $tmpArr );
            $tmpStr = sha1( $tmpStr );

            if( $tmpStr == $signature ){
                return true;
            }else{
                return false;
            }
        }
        if(checkSignature()){
            echo $echostr;
        }else{
            echo " Authentication failed ";
        }