C#

private void textboxInteger_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
		{			
			validate.txtIntValidate(txtPhone.text)		
		}

class Validate
    {
        public bool txtIntValidate(string txt)
        {
            if (!Char.IsDigit(e.KeyChar) && e.KeyChar != (char)8)
            {
                e.Handled = true; // input is not passed on to the control(TextBox)                
            }            
        }
    }

private void writeData()
        {
            StreamWriter writer = new StreamWriter(saveMonsterSetBase.FileName, false);

            for (int i = 0; i < MonsterSetBaseDataArray.Count; i++)
            {
                writer.Write(MonsterSetBaseDataArray[i]);
            }

            writer.Close();
        }

IntPtr hDesktopListView = IntPtr.Zero;
IntPtr hProgman = (IntPtr)FindWindow("Progman", null);
IntPtr hDesktop = IntPtr.Zero;

if (hProgman != IntPtr.Zero)
{
    hDesktop = FindWindowEx(hProgman, IntPtr.Zero, "SHELLDLL_DefView", null);
    if (hDesktop != IntPtr.Zero)
    {
        hDesktopListView = FindWindowEx(hDesktop, IntPtr.Zero, "SysListView32", null);
    }
}

return hDesktopListView;