windows form中将服务器端的文件保存到客户端

public static class FileHelper
    {
        /// 

        /// 下载服务器文件至客户端，Create By Wangjianhui
        /// 
        /// 被下载的文件地址，绝对路径
        /// 另存放的目录
        public static void DownloadFileToLocal(string URL, string DirFilePath,out string errorMeesage)
        {
            WebClient client = new WebClient();
            string fileName = URL.Substring(URL.LastIndexOf("\\") + 1);  //被下载的文件名
            //string Path = Dir + fileName;   //另存为的绝对路径＋文件名

            try
            {
                WebRequest myre = WebRequest.Create(URL);
                errorMeesage = String.Empty;
            }
            catch (Exception e1)
            {
                errorMeesage = e1.Message;
                //MessageBox.Show(e1.Message, "Error");
            }

            try
            {
                client.DownloadFile(URL, DirFilePath);
                errorMeesage = String.Empty;
            }
            catch (Exception e2)
            {
                errorMeesage = e2.Message;
                //MessageBox.Show(e2.Message, "Error");
            }
        }
    }

     private void btnSave_Click(object sender, EventArgs e)
        {
             string sourceFile="E:\\FileFolder\\123.fff";
            System.IO.FileInfo f = new System.IO.FileInfo(sourceFile);
            string sourceFileName = f.Name;//原文件名称

            string dirFilePath = string.Empty;
            saveFileDialogForFFF.FileName = sourceFileName;
            saveFileDialogForFFF.Filter = "电子书文件（.fff）|*.fff";
            if (saveFileDialogForFFF.ShowDialog() == DialogResult.OK)
            {
                dirFilePath = saveFileDialogForFFF.FileName;
            }
           string errorMessage = string.Empty;
           FileHelper.DownloadFileToLocal(sourceFile, dirFilePath, out errorMessage);
           if (!string.IsNullOrEmpty(errorMessage))
           {
               MessageBox.Show(errorMessage);
           }
           else
           {
               MessageBox.Show("The file has been saved successfully");
           }
        
        }