Google翻译PHP接口

<?php   
    /* Google翻译PHP接口  */

    class Google_API_translator {    
        public $url = "http://translate.google.com/translate_t";   
        public $text = "";//翻译文本   
        public $out = ""; //翻译输出 
        public $lang_src = "";//要翻译的语言
        public $lang_des = "";//翻译成的语言
           
        function setText($text){   
            $this->text = $text;   
        }   
  
  function setLang($lang_src,$lang_des){
   $this->lang_src = $lang_src;
   $this->lang_des = $lang_des;
  }
           
        function translate() {    
            $this->out = "";    
               
            $gphtml = $this->postPage($this->url, $this->text,$this->lang_src,$this->lang_des);    
            $out = substr($gphtml, strpos($gphtml, "<div id=result_box dir=\"ltr\">"));   
            $out = substr($out, 29);   
            $out = substr($out, 0, strpos($out, "</div>"));   
               
            $this->out = $out;   
            return $this->out;    
        }    
           
        function postPage($url, $text,$lang_src,$lang_des) {    
            $html ='';    
               
            if($url != "" && $text != ""&&$lang_src != ""&&$lang_des != "") {    
                $ch = curl_init($url);    
                curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);    
                curl_setopt($ch, CURLOPT_HEADER, 1);    
                curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);    
                curl_setopt($ch, CURLOPT_TIMEOUT, 15);    
                   
                /*  
                 *hl - 界面语言 此处无用。  
                 *langpair - src lang to dest lang  
                 *ie - urlencode的编码方式?  
                 *text - 要翻译的文本  
                 */  
                $fields = array('hl=zh-CN', 'langpair='.$lang_src.'|'.$lang_des, 'ie=UTF-8','text='.urlencode(mb_convert_encoding($text, 'UTF-8', 'GB2312')));   
                curl_setopt($ch, CURLOPT_POST, 1);   
                curl_setopt($ch, CURLOPT_POSTFIELDS, implode('&', $fields));                                                        
                   
                $html = curl_exec($ch);    
                if(curl_errno($ch)) $html = "";    
                curl_close ($ch);    
            }    
            return $html;    
        }    
    }    
  ?>