php 小程序获取渠道二维码 保存

function ppost($url,$arr){
   $post_data = json_encode($arr);
   $url=$url;
     $ch = curl_init();
     curl_setopt($ch, CURLOPT_POST, 1);
     curl_setopt($ch, CURLOPT_HEADER, 0);
     curl_setopt($ch, CURLOPT_URL,$url);
     curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);//这里也是那个是否接收返回值的设置

   curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
   curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);    // https请求 不验证证书和hosts
     curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
     $result = curl_exec($ch);
     curl_close($ch);
     return $result;
}
//将二进制以图片存入硬盘
function toimg($aa,$path,$filename){
      //将二进制转为图片
$imgDir = $path;
$filename=$filename;///要生成的图片名字  

$xmlstr =  $aa;
if(empty($xmlstr)) {
    $xmlstr = file_get_contents('php://input');
}  

$jpg = $xmlstr;//得到post过来的二进制原始数据
if(empty($jpg))
{
    echo 'nostream';
    exit();
}  

$file = fopen("./".$imgDir."/".$filename,"w");//打开文件准备写入
fwrite($file,$jpg);//写入
fclose($file);//关闭  

$filePath = './'.$imgDir."/".$filename;  

//图片是否存在
if(!file_exists($filePath))
{
    echo 'createFail'."---".$filePath;
    exit();
}
}
  $url = "https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=TOKEN";
  $data['scene'] = "666";    //二维码参数
  $data['width'] = "100";
//$data['page'] = "pages/index/index";
  $aa = ppost($url,$data);
  toimg($aa,'Public/tk_qrcode',time().".jpg");