netcore 从api下载文件到本地

public IActionResult HttpDownFile()
        {
            string url = "http://localhost:99/api/HttpFile/GetFile";
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.Method = "GET";
            byte[] fileBytes;
            using (WebResponse webRes = request.GetResponse())
            {
                int length = (int)webRes.ContentLength;
                HttpWebResponse response = webRes as HttpWebResponse;
                Stream stream = response.GetResponseStream();
                var contentdisposition = response.Headers["Content-Disposition"];
                var filename = Util.Midstr(contentdisposition, "filename=", ";");
                //读取到内存
                MemoryStream stmMemory = new MemoryStream();
                byte[] buffer = new byte[length];
                int i;
                //将字节逐个放入到Byte中
                while ((i = stream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    stmMemory.Write(buffer, 0, i);
                }
                fileBytes = stmMemory.ToArray();//文件流Byte
                FileStream fs = new FileStream("D:\\other\\Test\\"+filename, FileMode.OpenOrCreate);
                stmMemory.WriteTo(fs);
                stmMemory.Close();
                fs.Close();
                return Ok("D:\\other\\Test\\" + filename);
            }
        }

url是下载文件的地址