private void SecondaryExamForm_FormClosing(object sender, FormClosingEventArgs e)
{
if (MessageBox.Show(this, "确定要关闭当前窗体吗？是,请单击‘确定’\n按钮，否则，请单击‘取消’按钮。", "提示",
MessageBoxButtons.OKCancel, MessageBoxIcon.Question) == DialogResult.OK)
{
SecondaryExamForm SFrm = new SecondaryExamForm();
SFrm.Close();
}
else
{
e.Cancel = true;
}
}
private void 中级自测试题SToolStripMenuItem_Click(object sender, EventArgs e)
{
//隐藏父窗体上的标题文本
this.label1.Visible = false;
//隐藏父窗体上的修饰图片
this.pictureBox1.Visible = false;
//隐藏父窗体上的版权文本
this.label2.Visible = false;
//将MainForm窗体设置为父窗体，此行代码功能与步骤（1）等效，二者可取其一
//this.IsMdiContainer = true;
//实例化PrimaryExamForm
SecondaryExamForm PFrm = new SecondaryExamForm();
//调用方法Show方法，显示窗体PFrm
PFrm.MdiParent = this;
//调用Show方法，显示窗体PFrm
PFrm.Show();
}