一个SqlDataReader的用法，dr.IsDBNull(2)用来判断第几列是否为null

//=============================================================

// 方 法 名： selTestPage()

// 功能描述： 查看员工状态

// 输入参数：

// 返 回 值： int

// ==============================================================

public void selTestPage()

{

Session["examCode"] = GridView1.SelectedRow.Cells[0].Text;

//根据考试编号去查询此次考试的试卷参数

SqlConnection GetTestPageConn = CreateTestConection.getConnection();

SqlCommand GetTestPageCmd = new SqlCommand("Proc_GetPagePam", GetTestPageConn);

GetTestPageCmd.CommandType = CommandType.StoredProcedure;

SqlParameter examCode = new SqlParameter("@examCode", SqlDbType.Char, 5);

examCode.Value = GridView1.SelectedRow.Cells[0].Text;

GetTestPageCmd.Parameters.Add(examCode);

GetTestPageConn.Open();

SqlDataReader dr = GetTestPageCmd.ExecuteReader();

try

{

if (dr.Read())

{

if (!dr.IsDBNull(1))

{

Session["type"] = dr.GetString(1);//考题类型

}

if (!dr.IsDBNull(2))

{

Session["pageMark"] = dr.GetInt32(2);

}

if (!dr.IsDBNull(3))

{

Session["QuestionNum"] = dr.GetInt32(3);

}

if (!dr.IsDBNull(4))

{

Session["everyMark"] = dr.GetDouble(4);

}

if (!dr.IsDBNull(5))

{

Session["ExamTime"] = dr.GetInt32(5);

}

if (!dr.IsDBNull(6))

{

Session["EveryTime"] = dr.GetDouble(6);

}

}

dr.Close();

}

catch

{

GetTestPageCmd.Dispose();

GetTestPageConn.Close();

Response.Write("<script language='javascript' defer>alert('查询试卷参数出错，请重试！');</script>");

}

GetTestPageCmd.Dispose();

GetTestPageConn.Close();

}