Recommended video tutorial resources for WeChat public platform development by Chuanzhi and Dark Horse

<?php
include_once &#39;lib.inc.php&#39;;
  
$wcObj = new WeChat("YOUKUIYUAN");
$wcObj->wcValid();

<?php
/**
 * Description of wechat
 *
 * @author Administrator
 */
class WeChat extends WxApi{
  public $token = "";
  //put your code here
  public function __construct($token = "") {
    parent::__construct();
    $this->token = $token;
  }
  
  public function wcCheckSignature(){
    try{
      if (empty($this->token)) {
        throw new Exception(&#39;TOKEN is not defined!&#39;);
      }
        
      $signature = $_GET["signature"];
      $timestamp = $_GET["timestamp"];
      $nonce = $_GET["nonce"];
          
      $token = $this->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;
      }
    } 
    catch (Exception $e) {
      echo &#39;Message: &#39; .$e->getMessage();
    }
  }
    
  public function wcValid(){
    $echoStr = isset($_GET["echostr"]) && !empty($_GET["echostr"]) ? addslashes($_GET["echostr"]) : NULL;
    if(is_null($echoStr)){
      $this->wcMsg();
    }
    else{
      //valid signature , option
      if($this->wcCheckSignature()){
        echo $echoStr;
        exit;
      }
      else{
        exit();
      }
    }
  }
    
  public function wcMsg(){
    //get post data, May be due to the different environments
    $postStr = isset($GLOBALS["HTTP_RAW_POST_DATA"]) && !empty($GLOBALS["HTTP_RAW_POST_DATA"]) ? $GLOBALS["HTTP_RAW_POST_DATA"] : "";
    if(!empty($postStr)){
      libxml_disable_entity_loader(true);
      $postObj = simplexml_load_string($postStr, &#39;SimpleXMLElement&#39;, LIBXML_NOCDATA);
      $this->zcLog(TRUE,$postObj);
        
      $fromUsername = $postObj->FromUserName;
      $toUsername = $postObj->ToUserName;
      $MsgType = $postObj->MsgType;
        
      if($MsgType == &#39;event&#39;){//执行事件相应
        $Event = $postObj->Event;
        switch ($Event) {
          case &#39;subscribe&#39;://关注
            break;
          case &#39;unsubscribe&#39;://取消关注
            break;
          case &#39;SCAN&#39;://扫描
            break;
          case &#39;LOCATION&#39;://地址
            break;
          case &#39;CLICK&#39;://点击时间
            break;
          case &#39;VIEW&#39;://跳转
            break;
          case &#39;card_pass_check&#39;://卡券审核通过
            break;
          case &#39;card_not_pass_check&#39;://卡券审核失败
            break;
          case &#39;user_get_card&#39;://用户领取卡券
            break;
          case &#39;user_del_card&#39;://用户删除卡券
            break;
          case &#39;user_view_card&#39;://用户浏览会员卡
            break;
          case &#39;user_consume_card&#39;://用户核销卡券
            break;
          case &#39;merchant_order&#39;://微小店用户下单付款
            break;
          default:
            break;
        }
      }
      else{
        switch ($MsgType) {
          case &#39;text&#39;://文本格式
            break;
          case &#39;image&#39;://图片格式
            break;
          case &#39;voice&#39;://声音
            break;
          case &#39;video&#39;://视频
            break;
          case &#39;shortvideo&#39;://小视频
            break;
          case &#39;location&#39;://上传地理位置
            break;
          case &#39;link&#39;://链接相应
            break;
          default:
            break;
        }        
      }
        
      ////////////////////////////////////////////////////////////////////
      $keyword = trim($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 "暂时没有任何信息！";
      exit;
    }
  }
    
  //日志LOG
  public function zcLog($errcode , $errmsg){
    $this->returnAy = array();
    $this->returnAy[&#39;errcode&#39;] = $errcode;
    $this->returnAy[&#39;errmsg&#39;] = $errmsg;
    $this->returnAy[&#39;errtime&#39;] = date("Y-m-d H:i:s",time());
    $logfile = fopen("logfile_".date("Ymd",time()).".txt", "a+");
    $txt = json_encode($this->returnAy)."\n";
    fwrite($logfile, $txt);
    fclose($logfile);
    //return $this->returnAy;
  }
    
}