Use This Function
public void EmptyControlData(Control parent)
{
foreach (Control c in parent.Controls)
{
if ((c.GetType() == typeof(TextBox)))
{
((TextBox)c).Text = "";
}
if ((c.GetType() == typeof(DropDownList)))
{
((DropDownList)c).SelectedIndex = -1;
}
if (c.HasControls())
{
EmptyControlData(c);
}
}
}
Here parent is
this.