Imports System.Data.SqlClient
Public Class WebForm1
Inherits System.Web.UI.Page
Dim scon As New SqlConnection("server=localhost;database=northwind;uid=sa;pwd=123")
Dim sDA As SqlDataAdapter
Dim ds As DataSet
Dim currentPage As Integer '記錄著目前在哪一頁上
Dim maxPage As Integer '總共有多少頁
Const rowCount As Integer = 3 '一頁有多少行
Dim rowSum As Integer '總共有多少行
'表單代碼省略
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Not Page.IsPostBack Then
sDA = New SqlDataAdapter("select employeeid, lastname from employees order by employeeid", scon)
ds = New DataSet
Try
sDA.Fill(ds, "employees")
'擷取總共有多少行
rowSum = ds.Tables(0).Rows.Count
Catch ex As Exception
rowSum = 0
End Try
'如果沒有資料,退出過程
If rowSum = 0 Then Exit Sub
'計算出瀏覽資料的總頁數
If rowSum Mod rowCount > 0 Then
'有餘數要加1
maxPage = rowSum \ rowCount + 1
Else
'正好除盡
maxPage = rowSum \ rowCount
End If
currentPage = 1
'調用綁定資料過程
readpage(currentPage)
BindData()
Label2.Text = maxPage
'首頁和上一頁按鈕不可見
Button1.Visible = False
Button2.Visible = False
End If
End Sub
'建立一個綁定資料的過程
Sub BindData()
Repeater1.DataSource = ds
Repeater1.DataBind()
Label1.Text = currentPage
End Sub
'建立一個填充資料集的過程
Sub readpage(ByVal n As Integer)
sDA = New SqlDataAdapter("select employeeid, lastname from employees order by employeeid", scon)
ds = New DataSet
ds.Clear()
sDA.Fill(ds, (n - 1) * rowCount, rowCount, "employees")
End Sub
'首頁按鈕
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'上一頁按鈕
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'如果現在頁是第二頁,設定首頁和上一頁按鈕不可見
If Label1.Text > 2 Then
Button3.Visible = True
Button4.Visible = True
Else
Button1.Visible = False
Button2.Visible = False
Button3.Visible = True
Button4.Visible = True
End If
currentPage = Label1.Text - 1
readpage(currentPage)
BindData()
End Sub
'下一頁按鈕
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
'如果現在頁倒數第二頁,設定最後頁和下一頁按鈕不可見
If Label1.Text < Label2.Text - 1 Then
Button1.Visible = True
Button2.Visible = True
Else
Button1.Visible = True
Button2.Visible = True
Button3.Visible = False
Button4.Visible = False
End If
currentPage = Label1.Text + 1
readpage(currentPage)
BindData()
End Sub
'尾頁按鈕
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
'設定當前頁為最大頁數
currentPage = Label2.Text
readpage(currentPage)
BindData()
Button1.Visible = True
Button2.Visible = True
Button3.Visible = False
Button4.Visible = False
End Sub
End Class
表單介面如下所示: