private void button2_Click(object sender, EventArgs e)
{
if (Program.f2 == null || Program.f2.IsDisposed)
{
Program.f2 = new Form2();
}
Program.f2.Show();
Program.f2.BringToFront();
}
在close事件时要释放窗体对象;
Program.f2 =null;
Program.f3=null;