Translation function developed by PHP WeChat

public function responseMsg(){
   //get post data, May be due to the different environments
  $postStr = $GLOBALS["HTTP_RAW_POST_DATA"]; //接收微信发来的XML数据

  //extract post data
 if(!empty($postStr)){
    
   //解析post来的XML为一个对象$postObj
   $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
  
   $fromUsername = $postObj->FromUserName; //请求消息的用户
   $toUsername = $postObj->ToUserName; //"我"（订阅号）的公众号id
   $keyword = trim($postObj->Content); //用户发给订阅号的消息内容
   $time = time(); //时间戳
   $msgtype = 'text'; //消息类型：文本
   $textTpl = "<xml>
  <ToUserName><![CDATA[%s]]></ToUserName>
  <FromUserName><![CDATA[%s]]></FromUserName>
  <CreateTime>%s</CreateTime>
  <MsgType><![CDATA[%s]]></MsgType>
  <Content><![CDATA[%s]]></Content>
  </xml>";

   if($postObj->MsgType == &#39;event&#39;){ //如果XML信息里消息类型为event
    if($postObj->Event == &#39;subscribe&#39;){ //如果是订阅事件
     $contentStr = "欢迎";
     $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgtype, $contentStr);
     echo $resultStr;
     exit();
    }
   }

   $which = mb_substr($keyword, 0, 2, &#39;UTF-8&#39;);//获取要返回什么样的信息

   if($which== "翻译"){ //如果要进行翻译
    $fanyi = $which;
    $search = str_replace($fanyi, &#39;&#39;, $keyword); //要翻译的关键字

    $key = ""; //在有道API申请的key
    $keyfrom = ""; //与key对应
    $url = &#39;http://fanyi.youdao.com/openapi.do?keyfrom=&#39; . $keyfrom . &#39;&key=&#39; . $key . &#39;&type=data&doctype=json&version=1.1&q=&#39; . urlencode($search);//调用有道翻译API
    
    $json = file_get_contents($url);//也可以用curl来获取
    $res = json_decode($json, true);

    /**
     * 以下从返回的数据中提取翻译结果
     */
    $contentStr = &#39;【查询】&#39; . $res[&#39;query&#39;] . "\n";
    $contentStr .= "【翻译】\n" . $res[&#39;translation&#39;][0] . "\n";

    $str = &#39;&#39;;
    foreach($res[&#39;basic&#39;][&#39;explains&#39;] as $v){
     $str .= $v . "\n";
    }
    $contentStr .= "【基本释义】\n" . $str;


    if(isset($res[&#39;web&#39;])){

     foreach($res[&#39;web&#39;] as $kk=>$vv){
      sort($vv);
      $res[&#39;web&#39;][$kk] = $vv; //调节字段顺序
     }

     $str = &#39;&#39;;
     foreach($res[&#39;web&#39;] as $v){
      foreach($v as $k2=>$v2){
       if($k2 == 0){
        $str .= "【". $v2 ."】\n";
       }else{
        foreach($v2 as $v3){
         $str .= $v3 ."\n";
        }
       }
      }
     }
     $contentStr .= "【网络释义】\n" . $str;     
    }

    $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgtype, $contentStr);
    echo $resultStr;
    exit(); 

   }