private void GetFiles( )
DriveInfo allDrive = DriveInfo.GetDrives();
//Gets the drive names of all drives in the computer
foreach (DriveInfo d in allDrive)
string b = d.Name.ToString();
var filename = Directory.GetFiles(b, “*.*”, SearchOption.TopDirectoryOnly);
// it returns the all file with the path whose type is “*.*”.
foreach (string a in filename)