private void Button_Click(object sender, System.EventArgs e)
{
Button btn = (Button)sender;
string str = btn.Text;
switch (str)
{
case "Copy":
if (TextBox1.SelectionLength > 0)
{
TextBox1.Copy();
}
break;
case "Cut":
if (TextBox1.SelectionLength > 0)
{
TextBox1.Cut();
}
break;
case "Paste":
TextBox1.Paste();
break;
case "Undo":
TextBox1.Undo();
break;
}
}