L'impaginazione in DataList non funziona

Question

Ho DataList sulla mia pagina per mostrare i record provenienti dal database. Ho seguito il tutorial this per implementare la paginazione con DataList.

Mostra 5 record sulla prima pagina ma nella pagina successiva, Datalist viene caricato vuoto. Riesco a vedere il valore delle modifiche alla pagina corrente facendo clic sui pulsanti Avanti e Indietro.

seguito è il mio codice della pagina aspx:

<asp:DataList ID="DataList1" runat="server"> 
    <HeaderTemplate> 
     <table class="TicketTableInner"> 
      <tr> 
       <td class="ticketlistheaderrow" align="left" valign="middle" width="8%">Ticket ID</td> 
       <td class="ticketlistheaderrow" align="left" valign="middle" width="21%">Category</td> 
       <td class="ticketlistheaderrow" align="left" valign="middle" width="41%">Problem</td> 
       <td class="ticketlistheaderrow" align="left" valign="middle" width="15%">Create Date</td> 
       <td class="ticketlistheaderrow" align="left" valign="middle" width="15%">Reply Date</td> 
       </tr> 
    </HeaderTemplate> 
    <ItemTemplate> 
       <tr class="TicketRow<%#Eval("IsReadString")%>" onclick="UpdateTicketID('<%#Eval("TicketIDD")%>')"> 
       <td class="ticketlistRowItem<%#Eval("IsReadString")%>"><%#Eval("TicketIDFROMDB")%></td> 
       <td class="ticketlistRowItem<%#Eval("IsReadString")%>"><%#TrimLenght(Eval("Category"), 30)%></td> 
       <td class="ticketlistRowItem<%#Eval("IsReadString")%>"><%#TrimLenght(Eval("Problem"), 70)%></td> 
       <td class="ticketlistRowItem<%#Eval("IsReadString")%>"><%#Eval("CreatedDate")%></td> 
       <td class="ticketlistRowItem<%#Eval("IsReadString")%>"><%# ProcessMyDataItemForNA(Eval("RepliedDate"))%></td> 
      </tr> 
    </ItemTemplate> 
    <FooterTemplate> 
    </table> 
    </FooterTemplate> 
</asp:DataList> 
    <table class="style1"> 
      <tr> 
      <td class="style2"> 
       <asp:LinkButton ID="LinkButton2" runat="server" 
        OnClick="LinkButton2_Click">Next</asp:LinkButton> 
      </td> 
      <td> 
       <asp:LinkButton ID="LinkButton3" runat="server" 
        OnClick="LinkButton3_Click">Previous</asp:LinkButton> 
      </td> 
     </tr> 
    </table> 

E segue è codice dal codice dietro:

Imports System.Data 
Imports System.Configuration 
Imports System.Data.SqlClient 
Partial Class supportTickets_myTickets 
    Inherits System.Web.UI.Page 
    Public TicketStatus As String = "" 
    Public TicketID As String = "" 
    Dim pg As Integer = 0 

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load 
     If Not IsPostBack Then 
      CurrentPageIndex = 0 
      showData() 
     Else 
     End If 
    End Sub 

    Private Function GetDataTable() As DataTable 
     '//This function returns record from database in the form of dataTable 
    End Function 


    Private Sub showData() 
     Dim pgd As New PagedDataSource() 
     Dim ds As DataSet = GetDataSet() 
     pgd.DataSource = ds.Tables(0).DefaultView 
     pgd.AllowPaging = True 
     pgd.PageSize = 5 
     pgd.CurrentPageIndex = CurrentPageIndex 

     LinkButton2.Enabled = Not (pgd.IsLastPage) 
     LinkButton3.Enabled = Not (pgd.IsFirstPage) 

     DataList1.DataSource = pgd 
     DataList1.DataBind() 
    End Sub 


    Public Property CurrentPageIndex() As Integer 
     Get 
      If ViewState("pg") Is Nothing Then 
       Return 0 
      Else 
       Return Convert.ToInt16(ViewState("pg")) 
      End If 
     End Get 
     Set(value As Integer) 
      ViewState("pg") = value 
     End Set 
    End Property 


    Protected Sub LinkButton2_Click(sender As Object, e As EventArgs) 
     CurrentPageIndex += 1 
     showData() 
    End Sub 
    Protected Sub LinkButton3_Click(sender As Object, e As EventArgs) 
     CurrentPageIndex -= 1 
     showData() 
    End Sub 

End Class 

Answer 1

Bind DataList dal paging dataSource

public int PageNumber 
     { 
      get 
      { 
       if (ViewState["PageNumber"] != null) 
        return Convert.ToInt32(ViewState["PageNumber"]); 
       else 
        return 0; 
      } 
      set 
      { 
       ViewState["PageNumber"] = value; 
      } 
     } 



private void BindListing() 
     { 
      DataTable dt = Method which return datatable; 
      if (dt.Rows.Count <= 0) 
      { 
       lnknext.Visible = false; 
       lnkPrevious.Visible = false; 
       ScriptManager.RegisterStartupScript(this, this.GetType(), "Error", "alert('No records found!!!.');", true); 
       return; 
      } 
      PagedDataSource pgitems = new PagedDataSource(); 
      DataView dv = new DataView(dt); 
      pgitems.DataSource = dv; 
      pgitems.AllowPaging = true; 
      pgitems.PageSize = 10; 
      pgitems.CurrentPageIndex = PageNumber; 

      DataList1.DataSource = pgitems; 
      DataList1.DataBind(); 

     } 



protected void lnkPrevious_Click(object sender, EventArgs e) 
     { 
      PageNumber -= 1; 
      BindListing(); 
     } 
     protected void lnknext_Click(object sender, EventArgs e) 
     { 

      PageNumber += 1; 
      BindListing(); 
     } 



protected void Page_Load(object sender, EventArgs e) 
     {  
      if (!IsPostBack) 
      { 
       BindListing(); 
      } 

     } 

spero sopra esempio sarà d'aiuto ..