else  // 否则弹出交卷提示，打开答题结果窗体
            {
                tmrCostTime.Stop();
                MessageBox.Show("时间到了，该交卷了！","提示",
                          MessageBoxButtons.OK, MessageBoxIcon.Warning);
                QuizResultForm quizResultForm = new QuizResultForm();
                quizResultForm.MdiParent = this.MdiParent;
                quizResultForm.Show();
                this.Close();
            }
        }
3) 题库及试卷管理模块源代码
public partial class QuestionListForm : Form
    {
        private SqlDataAdapter dataAdapter;   // 数据适配器
        private DataSet dataSet;              // 数据集

        public QuestionListForm()
        {
            InitializeComponent();
        }

        // 窗体加载时，填充数据集，打印内容
        private void QuestionListForm_Load(object sender, EventArgs e)
        {
            // 查询数据库用的SQL语句
            string sql = "select QuestionId,Question,OptionA,OptionB,OptionC,OptionD,Answer,Difficulty,SubjectId from Question";
            // 创建数据适配器对象
            dataAdapter = new SqlDataAdapter(sql, DBHelper.connection);
            // 创建数据集对象
            dataSet = new DataSet("MySchool");
            // 填充数据集
            dataAdapter.Fill(dataSet, "Question");

            // 指定DataGridView的数据源
            dgvQuestion.DataSource = dataSet.Tables["Question"];
        }

        private void btnClose_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        private void btnSave_Click(object sender, EventArgs e)
        { C#高职计算机导论考试系统设计与实现(20):http://www.751com.cn/jisuanji/lunwen_181.html