/// <summary>
/// 断点续传 服务端保存文件代码
/// </summary>
/// <returns></returns>
[HttpPost]
public bool UploadEcgData()
{
    bool result = false;
    FileStream fStream = null;
    BinaryReader bReader = null;
    try
    {
        long offset = 0;  //客户端定义，从X开始往后写，该值由服务端GetFileLength方法提供
        IEnumerable<string> hasOffsetList = new List<string>();
        bool hasOffset = Request.Headers.TryGetValues("Offset", out hasOffsetList);
        if (hasOffset && hasOffsetList.Any())
        {
            long.TryParse(hasOffsetList.First(), out offset);
        }
        HttpPostedFile file = HttpContext.Current.Request.Files[0];
        //设置文件存放路径 
        string dir = HttpContext.Current.Server.MapPath(@"~\UploadFiles");
        int upLoadLength = Convert.ToInt32(file.InputStream.Length);
        fStream = new FileStream(dir + "\\" + file.FileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
        //偏移指针
        fStream.Seek(offset, SeekOrigin.Begin);

        //从客户端的请求中获取文件流
        bReader = new BinaryReader(file.InputStream);
        byte[] data = new byte[upLoadLength];
        bReader.Read(data, 0, upLoadLength); //将上传文件流读到byte[]中
        fStream.Write(data, 0, upLoadLength);//将byte[]写到文件中，
        result = true;
    }
    catch (Exception ex)
    {
        logger.Error(ex, ex.Message);
        result = false;
    }
    finally
    {
        if (fStream != null)
        {
            //释放流
            fStream.Close();
        }
        if (bReader != null)
        {
            bReader.Close();
        }
    }
    return result;
}