[DllImport("user32.dll", EntryPoint = "SystemParametersInfo")]public static extern int SystemParametersInfo(int uAction,int uParam,string lpvParam,int fuWinIni);/// <summary>/// 設置圖片桌面/// </summary>/// <param name="randomFileName"></param>public static void UpdateWindowsDesk(int randomFileName){          var PicName = AppDomain.CurrentDomain.BaseDirectory + @"UpLoadImages\"+ randomFileName+".bmp";SystemParametersInfo(20, 0, PicName, 0x2);}

 /// <summary>/// 上傳文件/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void UploadImage_Click(object sender, EventArgs e){//初始化openFileDialogOpenFileDialog ofd = new OpenFileDialog();ofd.Title = "请选择要上传的图片";ofd.Filter = "图像文件(*.jpg;*.gif;*.png)|*.jpg;*.gif;*.png";ofd.Multiselect = false;if (ofd.ShowDialog() == DialogResult.OK){string oldFilePath = ofd.FileName;int position = oldFilePath.LastIndexOf("\\");string OldfileName = oldFilePath.Substring(position + 1);string[] splitName = oldFilePath.Split('.');string ext = splitName[splitName.Length - 1];var index = 1;cc: string newName = index + ".bmp";// + ext;//判断根目录下是否含有指定文件夹，若没有则创建一个新的string path = AppDomain.CurrentDomain.BaseDirectory + "/UpLoadImages";DirectoryInfo di = new DirectoryInfo(path);if (!di.Exists){di.Create();}string newFilePath = AppDomain.CurrentDomain.BaseDirectory + "/UpLoadImages/" + newName;if (File.Exists(newFilePath)){index = index + 1;goto cc;}File.Copy(oldFilePath, newFilePath, false);Image img = Image.FromFile(newFilePath);//tureBox1.Image = img;MessageBox.Show("上传成功", "Tip");}}

 /// <summary>/// 讀取文件夾下文件數量/// </summary>/// <param name="dirInfo"></param>/// <returns></returns>public static int GetFilesCount(DirectoryInfo dirInfo){int totalFile = 0;//totalFile += dirInfo.GetFiles().Length;//获取全部文件totalFile += dirInfo.GetFiles("*.bmp").Length;//获取某种格式foreach (System.IO.DirectoryInfo subdir in dirInfo.GetDirectories()){totalFile += GetFilesCount(subdir);}return totalFile;}