Asp.net中通过Button打开另一个的frm

private void Form1_FormClosing(object sender, FormClosingEventArgs e){DialogResult re = MessageBox.Show("确定离开吗","询问",MessageBoxButtons.YesNo,MessageBoxIcon.Question);if(re==DialogResult.No){e.Cancel = true;}}private void button1_Click(object sender, EventArgs e){this.Close(); //点击该button后实现关闭窗口}private void button2_Click(object sender, EventArgs e){Form2 frm = new Form2();frm.ShowDialog(); //showdialog 模态出来的窗体如果想关闭主窗体 就必须先关闭模态窗体//frm.Show();// show 可以再次点击主窗口来打开无数个窗口 而不会强制停留在新窗口}