datalist在绑定时，每显示5行就插入一个空行。

Dim intNum As Integer = 0     '用来计算数据绑定到第几行

    Dim identity As Integer = 0　　'用来计算前面添加了多少个空行

    Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView1.RowDataBound

        If e.Row.RowType = DataControlRowType.DataRow Then

            intNum = intNum + 1

            If intNum Mod 2 = 0 And intNum <> 10 Then  'mod 2这里用的是2你可以改为5 ;10为没页显示的行数

                Dim grv As GridViewRow = New GridViewRow(-1, -1, DataControlRowType.DataRow, DataControlRowState.Normal)

                Dim cell As TableCell = New TableCell

                cell.Text = " "

                grv.Cells.Add(cell)

                GridView1.Controls(0).Controls.AddAt(intNum + identity + 1, grv)

                identity += 1

            End If

        End If

    End Sub