datagirdview和listview,删改查sqlserver数据库的小结

        //创建DBhelper数据库链接文件
        private static string sqlcon = "server=.;database=myschool;uid=sa;pwd=sa";
        public static SqlConnection connection = new SqlConnection(sqlcon);
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            //首先是lv控件的列表显示 ,(listview)
            // 清空当前lv表中内容
            listview.Items.Clear();
            string sql = "select * from question";
            //引用DBhelper中的数据库链接
            SqlCommand command = new SqlCommand(sql,DBhelper.connection);
            //打开数据库,并用dr读取记录
            DBhelper.connection.Open();
            SqlDataReader dr = command.ExecuteReader();
            while (dr.Read())
            {
                ListViewItem lvi = new ListViewItem(dr["Question"].ToString());
                lvi.SubItems.AddRange(new string[] { dr["Answer"].ToString(), dr["Difficulty"].ToString(), dr["SubjectId"].ToString(), dr["OptionA"].ToString(), dr["OptionB"].ToString(), dr["OptionC"].ToString(), dr["OptionD"].ToString() });