How to delete folder and subfolder in device?

[201211]

I test this code and debug on device for the purpose of trying to delete folder:

using System;
using System.IO;

class Test 
{
	
    public static void Main() 
    {
        // Specify the directories you want to manipulate.
        string path = @"\MyDir";
        string subPath = @"\MyDir\temp";

        try 
        {
            // Determine whether the directory exists.
            if (!Directory.Exists(path)) 
            {
                // Create the directory.
                Directory.CreateDirectory(path);
            }


            if (!Directory.Exists(subPath)) 
            {
                // Create the directory.
                Directory.CreateDirectory(subPath);
            }

            // This will succeed because subdirectories are being deleted.
            MessageBox.Show("I am about to attempt to delete {0}", path);
            Directory.Delete(path, true);
            MessageBox.Show("The Delete operation was successful.");

        } 
        catch (Exception e) 
        {
            MessageBox.Show("The process failed: {0}", e.ToString());
        } 
        finally {}
    }
}

but it not delete the folder after debug on device although appear message box delete operation success...
any idea?