ResetForm()

private void ResetForm()
{
foreach (string ControlID in Request.Form.AllKeys)
{
if (ControlID.Contains("ddl"))
{
((DropDownList)form1.FindControl(ControlID)).SelectedIndex = -1;
}
else if (ControlID.Contains("txt"))
{
((TextBox)form1.FindControl(ControlID)).Text = string.Empty;
}
}
}