微信企业号获取Token的函数(Access_token缓存版)

function getAccessToken($corpId,$secret) {	
	
    $data = json_decode(get_php_file("access_token.php"));
	
    if ($data->expire_time < time()) {

        $GetTokenUrl = 'https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid='.$corpId.'&corpsecret='.$secret.'';
        $gettoken = httpGet($GetTokenUrl);
        $jsontoken = json_decode($gettoken);
        $access_token = $jsontoken->access_token;

        if ($access_token) {
			
           $data->access_token = $access_token;
		   $data->expire_time = time() + 7000;
           set_php_file("access_token.php", json_encode($data));
		   
        }
		
    } 
	
	else {
		
      $access_token = $data->access_token;
	  
    }
	
	return $access_token;
}