這個作法是將資料庫的資料先存到DataTable，然後程式碼中會設定每一頁顯示幾筆資料，並算出目前從第幾筆資料到第幾筆資料，換頁之後在計算出，下一頁該從第幾筆到第幾筆資料，只是這個作法在每一次換頁的時候，都會重新和資料庫拿資料。
前端程式碼
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="test_pagination.aspx.vb" Inherits="test_test_pagination" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title></title>
<link rel="stylesheet" href="../css/bootstrap.css" />
<script src="../js/jquery-1.11.3.js"></script>
<script src="../js/bootstrap.js"></script>
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
</head>
<body>
<form id="form1" runat="server">
<div>
<nav id="nav_pagehead" runat="server">
<ul id="paging_head" runat="server" class="pagination">
</ul>
</nav>
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
<nav>
<ul id="paging_foot" runat="server" class="pagination">
</ul>
</nav>
</div>
</form>
</body>
</html>
後端程式碼
Imports System.Data
Imports System.Data.SqlClient
Partial Class test_test_pagination
Inherits System.Web.UI.Page
Dim str_sql As String = String.Empty
Dim def_dt As DataTable = Nothing
'=============================
Dim prows As Integer = 20 '每一頁多少筆數(此處100筆分成一頁)
Dim this_page As Integer = 1 '目前在第幾頁
Dim maxpage As Integer = 10 '最多顯示頁數(不變動)
Dim showpage As Integer = 10 '計算目前顯示頁數
Sub Call_get_paging()
'取得目前分頁頁數
If (Not Request("p") Is Nothing) Then
If Regex.IsMatch(Request("p").ToString, "^\d+$") = False Then '數字會回傳true
'不是數字,設定回1
this_page = 1
Else
this_page = CInt(Request("p").ToString)
End If
Else
this_page = 1
End If
End Sub
Private Sub form1_Load(sender As Object, e As EventArgs) Handles form1.Load
If Not Page.IsPostBack Then
def_dt = Nothing
str_sql = "select TOP 5000 * from Student"
'假設def_dt已經有資料了，請自行換成自己的DataTable
def_dt = queryDataTable2(str_sql)
Call_get_paging() '取得目前的頁數，傳到this_page變數
Dim rows_count As Integer = 0 '資料的總筆數
rows_count = def_dt.Rows.Count
Dim dt1 As DataTable = CopyData_NewDataTable(def_dt, this_page, prows)
If Not dt1 Is Nothing Then
GridView1.DataSource = dt1
GridView1.DataBind()
GridView1.CssClass = "table table-bordered"
End If
def_dt.Clear()
def_dt.Dispose()
def_dt = Nothing
'Response.Write("total_rows=" & total_rows & "<br/>")
If rows_count > 0 Then
's1開始頁數;tot_x1 全部的頁數
Dim s1 As Integer = 1, tot_x1 As Integer = 0
tot_x1 = Fix(rows_count / prows) '總筆數/每一頁多少筆數
'總筆數 求餘數,餘數>0就加1頁
If (CInt(rows_count) Mod prows) > 0 Then
tot_x1 = tot_x1 + 1
End If
'==========================
'頁數變動
If this_page >= 7 Then
If ((tot_x1 + 1) - ((this_page - 6) + 1)) >= maxpage Then
s1 = (this_page - 6) + 1
showpage = maxpage + (this_page - 6)
Else
s1 = ((this_page - 6) + 1) + (((tot_x1 + 1) - ((this_page - 6) + 1)) - maxpage)
showpage = tot_x1
End If
Else
'預設
s1 = 1 '第一頁開始
showpage = maxpage '顯示的頁數
End If
'==========================
If tot_x1 > 1 Then
Dim str_ago As String = String.Empty, str_back As String = String.Empty, str_num As String = String.Empty
Dim str_navpag As String = String.Empty, str_navpag_laquo As String = String.Empty, str_navpag_ago As String = String.Empty, str_navpag_back As String = String.Empty, str_navpag_raquo As String = String.Empty
For i As Integer = s1 To tot_x1
str_num = CStr(i)
If str_num.Length = 1 Then
str_num = "0" & str_num
End If
If i = this_page Then
str_navpag = str_navpag & "<li class=" & Chr(34) & "active" & Chr(34) & "><a>" & str_num & "<span class=" & Chr(34) & "sr-only" & Chr(34) & ">(current)</span></a></li>"
If i > 1 Then
str_navpag_ago = "<li><a href=" & Chr(34) & "test_pagination.aspx?p=" & (i - 1) & Chr(34) & " aria-label=" & Chr(34) & "Previous" & Chr(34) & "><span aria-hidden=" & Chr(34) & "true" & Chr(34) & "><</span></li>"
If i > 2 Then
str_navpag_laquo = "<li><a href=" & Chr(34) & "test_pagination.aspx?p=1" & Chr(34) & " aria-label=" & Chr(34) & "Previous" & Chr(34) & "><span aria-hidden=" & Chr(34) & "true" & Chr(34) & ">«</span></li>"
End If
End If
If i < tot_x1 Then
str_navpag_back = "<li><a href=" & Chr(34) & "test_pagination.aspx?p=" & (i + 1) & Chr(34) & " aria-label=" & Chr(34) & "Next" & Chr(34) & "><span aria-hidden=" & Chr(34) & "true" & Chr(34) & ">></span></li>"
If (tot_x1 - i) > 2 Then
str_navpag_raquo = "<li><a href=" & Chr(34) & "test_pagination.aspx?p=" & tot_x1 & Chr(34) & " aria-label=" & Chr(34) & "Next" & Chr(34) & "><span aria-hidden=" & Chr(34) & "true" & Chr(34) & ">»</span></li>"
End If
End If
Else
str_navpag = str_navpag & "<li><a href=" & Chr(34) & "test_pagination.aspx?p=" & i & Chr(34) & ">" & str_num & "</a></li>"
End If
If i = showpage Then
Exit For
End If
Next
Me.paging_head.InnerHtml = str_navpag_laquo & str_navpag_ago & str_navpag & str_navpag_back & str_navpag_raquo
Me.paging_foot.InnerHtml = str_navpag_laquo & str_navpag_ago & str_navpag & str_navpag_back & str_navpag_raquo
Else
Me.nav_pagehead.Attributes.Add("Style", "display:none;")
Me.paging_head.InnerHtml = ""
Me.paging_foot.InnerHtml = ""
End If
Else
Me.nav_pagehead.Attributes.Add("Style", "display:none;")
Me.paging_head.InnerHtml = ""
Me.paging_foot.InnerHtml = ""
End If
End If
End Sub
Function CopyData_NewDataTable(ByVal def_dt1 As DataTable, ByVal this_page As Integer, ByVal get_count As Integer) As DataTable
Dim New_dt As DataTable = Nothing
If Not def_dt1 Is Nothing Then
'從第幾筆開始，第幾筆結束
Dim data_Start_count As Integer = 0, data_End_count As Integer = 0
data_Start_count = (this_page * get_count) - get_count + 1
data_End_count = this_page * get_count
New_dt = def_dt1.Clone() '將table的結構複製到新的DataTable
For y1 As Integer = data_Start_count To data_End_count
If (y1 - 1) > (def_dt1.Rows.Count - 1) Then
Exit For
Else
New_dt.ImportRow(def_dt1.Rows(y1 - 1))
End If
Next
Return New_dt
Else
Return Nothing
End If
End Function
End Class
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