c# - 如何在asp gridview中使用分页模板进行自定义分页？

Question

假设我想创建像“> 1 2 3 4 5 6 <”这样的分页，我决定在 gridview 中使用分页模板，这就是我所做的:

aspx 文件:

 <asp:GridView ID="gvDept" runat="server" CellPadding="4" ForeColor="Black" 
                      GridLines="Horizontal" AutoGenerateColumns="False" BackColor="White" 
                      BorderColor="#CCCCCC" BorderStyle="None" BorderWidth="1px"
                      AllowSorting="True" AllowPaging="True" AllowCustomPaging="True" 
                      DataSourceID="DS" DataKeyNames="departementcode" PageSize="3" OnRowCommand="gvDept_RowCommand">   
                      <Columns>
                          <asp:TemplateField>
                             <HeaderTemplate>
                                 <asp:CheckBox runat="server" ID="cbSelectAll" onclick="SelectAll(this)"></asp:CheckBox> 
                                <%-- <asp:CheckBox runat="server" ID="cbAll" OnCheckedChanged="cbAll_CheckedChanged" AutoPostBack="true"></asp:CheckBox>--%>
                             </HeaderTemplate>
                             <ItemTemplate>
                                 <asp:CheckBox runat="server" ID="cbSelectOne"></asp:CheckBox>
                             </ItemTemplate>
                          </asp:TemplateField>
                          <asp:HyperLinkField text="Edit" DataNavigateUrlFields="departementcode" 
                                DataNavigateUrlFormatString="ManageDepartement.aspx?flag=edit&amp;departementcode={0}" />
                          <asp:TemplateField ShowHeader="False">
                              <ItemTemplate>
                                  <asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="False" CommandName="Delete" 
                                      OnClientClick="return confirm ('Are you sure?');" Text="Delete">
                                  </asp:LinkButton>
                              </ItemTemplate>
                              <ItemStyle ForeColor="Red" />
                          </asp:TemplateField>
                          <asp:BoundField DataField="departementcode" HeaderText="Departement Code" ReadOnly="True" SortExpression="departementcode" />
                          <asp:BoundField DataField="departementname" HeaderText="Departement Name" SortExpression="departementname" />
                          <asp:BoundField DataField="createby" HeaderText="Create By" SortExpression="createby" />
                          <asp:BoundField DataField="createdate" HeaderText="Create Date" SortExpression="createdate" />
                          <asp:BoundField DataField="updateby" HeaderText="Update By" SortExpression="updateby" />
                          <asp:BoundField DataField="lastupdate" HeaderText="Last Update" SortExpression="lastupdate" />
                        </Columns>
                        <FooterStyle BackColor="#CCCC99" ForeColor="Black"/>
                        <HeaderStyle BackColor="#333333" Font-Bold="True" ForeColor="White" />
                       <PagerSettings Mode="Numeric" />
                        <PagerStyle BackColor="White" ForeColor="Black" HorizontalAlign="Center" CssClass="paging"/>
                        <PagerTemplate>

                       </PagerTemplate>
                        <RowStyle BorderColor="White"/>
                        <SelectedRowStyle BackColor="#CC3333" Font-Bold="True" ForeColor="White" />
                        <SortedAscendingCellStyle BackColor="#F7F7F7" />
                        <SortedAscendingHeaderStyle BackColor="#4B4B4B" />
                        <SortedDescendingCellStyle BackColor="#E5E5E5" />
                        <SortedDescendingHeaderStyle BackColor="#242121" />
                    </asp:GridView>
                    <asp:LinqDataSource ID="DS" runat="server" ContextTypeName="Admin.AirAsiaDCDataContext"
                                             EntityTypeName="" TableName="departements" EnableDelete="True" OnDeleted="DS_Deleted">
                    </asp:LinqDataSource>

然后我也将此代码放入 C# 中:

 protected void Page_Load(object sender, EventArgs e)
        {
                AirAsiaDCDataContext dc = new AirAsiaDCDataContext();
                int dtcount = dc.departements.Count();
                int pgcount = 0;

                if (dtcount % 3 > 0)
                {
                    pgcount = (dtcount / 3) + 1;
                }
                else
                {
                    pgcount = pgcount / 3;
                }

                Button pagerBTN;

                for (int i = 1; i <= pgcount; i++)
                {
                    if(i == 1)
                    {
                        pagerBTN = new Button();
                        pagerBTN.ID = "btNext";
                        pagerBTN.Text = ">";
                        pagerBTN.CommandName = "Next";

                        gvDept.BottomPagerRow.Cells[0].Controls.Add(pagerBTN);
                    }

                    pagerBTN  = new Button();
                    pagerBTN.ID = "bt" + i;
                    pagerBTN.Text = i.ToString();
                    pagerBTN.CommandName = i.ToString();

                    gvDept.BottomPagerRow.Cells[0].Controls.Add(pagerBTN);

                    if (i == pgcount)
                    {
                        pagerBTN = new Button();
                        pagerBTN.ID = "btLast";
                        pagerBTN.Text = "<";
                        pagerBTN.CommandName = "Last";

                        gvDept.BottomPagerRow.Cells[0].Controls.Add(pagerBTN);
                    }
                }
        }

  protected void gvDept_RowCommand(object sender, GridViewCommandEventArgs e)
        {
            AirAsiaDCDataContext dc = new AirAsiaDCDataContext();
            int datacount = dc.departements.Count();
            int pagecount = 0;
            int prevIDX = 0;

            if (datacount % 3 > 0)
            {
                pagecount = (datacount / 3) + 1;
            }
            else
            {
                pagecount = datacount / 3;
            } 

            if (e.CommandName == "Next")
            {
                 if (gvDept.PageIndex < pagecount - 1)
                 {
                        prevIDX = gvDept.PageIndex;
                        gvDept.PageIndex = gvDept.PageIndex + 1;

                        if (prevIDX == pagecount - 2)
                        {
                            Button btn = (Button)gvDept.BottomPagerRow.Cells[0].FindControl("btNext");
                            btn.Visible = false;
                        }
                 }   
            }
            else if (e.CommandName == "Prev")
            {
                if (gvDept.PageIndex > 0)
                {
                    prevIDX = gvDept.PageIndex;
                    gvDept.PageIndex = gvDept.PageIndex - 1;

                    if (prevIDX == 1)
                    {
                        Button btn = (Button)gvDept.BottomPagerRow.Cells[0].FindControl("btPrev");
                        btn.Visible = false;
                    }
                }
            }
            else
            {
                gvDept.PageIndex = Convert.ToInt32(e.CommandName) - 1;
            }
        }

我的代码可以工作，但问题是，如果我单击其中一个分页按钮，在回发之前我生成的所有分页按钮完全消失后，我不明白我在这里做错了什么？任何更正？

Answer 1

在 GridView 中使用

OnPageIndexChanging="gvDept_PageIndexChanging"

在 .cs 文件中添加此代码以在每次页面索引更改时将数据绑定(bind)到 GridView 。

protected void gvDept_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
    gvDept.PageIndex = e.NewPageIndex;
    // write here function to bind the grid to the datasource
}

将此添加到 Page_Load 函数的开头，以便每次回发后数据都绑定(bind)到 GridView 。

if (!IsPostBack)
    {
        //function to bind the grid to data source
    }