class Wechat_base_api{
        
        private $appid='wx5d4b7d2e8bfd5793';
        private $appsecret='4379ef7213c36eae5dc2ab91f9f6aced';
        //构造函数
        public function __construct($appid,$appsecret)
        {
            $this->appid = $appid;
            $this->appsecret = $appsecret;
        }
        
    //获取access_token（支持自动更新凭证）
        public function get_access_token()
        {
            $this->last_time = 1408851194;
            $access_token = "jIGpovtFGZDXCB_K2vqDPTA05zP7VWZaKIHXC_qZDqEiSGONWfCzQ45fI9aksl2L188yhtPpNB61iOBS4TTtgw";

            if(time() > ($this->last_time + 7200))
            {
                //GET请求的地址
                $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={$this->appid}&secret={$this->appsecret}";
                 $access_token_Arr =  $this->https_request($url);
                 $this->last_time = time();
                 return $access_token_Arr['access_token'];            
            }

            return $access_token;
        }

//https请求（支持GET和POST）
        protected function https_request($url,$data = null)
        {
            $ch = curl_init();
            curl_setopt($ch,CURLOPT_URL,$url);
            curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
            if(!empty($data))
            {
                curl_setopt($ch,CURLOPT_POST,1);//模拟POST
                curl_setopt($ch,CURLOPT_POSTFIELDS,$data);//POST内容
            }
            $outopt = curl_exec($ch);
            curl_close($ch);
            $outopt = json_decode($outopt,true);
            return $outopt;
        }
}