如何给GridView增加行点击事件

写的webform
asp.net+vb.net

怎么给gridview整一个点击行的事件，后台获取该行的值，，要拿这在数据库里面查数据
不要多弄一行按钮

                            <asp:GridView ID="GridView1" runat="server" >
                                <Columns></Columns>
                            </asp:GridView>
                       

    Dim dtl As DataTable = New DataTable()
    Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
          dtl.Columns.Add("add1", GetType(String))
        dtl.Columns.Add("add2", GetType(String))

        For i As Integer = 1 To 5
            Dim b As DataRow = dtl.NewRow
            b(0) = "test" & i.ToString
            b(1) = "test" & i.ToString
            dtl.Rows.Add(b)
        Next

        'GridView1.ShowHeaderWhenEmpty = True
        GridView1.ShowHeader = False
        GridView1.DataSource = dtl
        GridView1.DataBind()
    End Sub

加一个行点击事件 然后后台根据sender来获取行数据