C#.net实现在Winform中从internet下载文件的方法

/// <summary>/// 下载文件/// </summary>/// <param name="URL">下载文件地址</param>/// <param name="Filename">下载后另存为（全路径）</param>private bool DownloadFile(string URL, string filename){  try  {    System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL);    System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse();    System.IO.Stream st = myrp.GetResponseStream();    System.IO.Stream so = new System.IO.FileStream(filename, System.IO.FileMode.Create);    byte[] by = new byte[1024];    int osize = st.Read(by, 0, (int)by.Length);    while (osize > 0)    {      so.Write(by, 0, osize);      osize = st.Read(by, 0, (int)by.Length);    }    so.Close();    st.Close();    myrp.Close();    Myrq.Abort();    return true;  }  catch (System.Exception e)  {    writeLogFile(e.Message, true);    return false;  }}