ObjectDataSourceを使ったページング

ASP.NET C#

ステートレスなビジネスロジックが一覧データと件数を同時に返すとき

件数を一時的に保持してObjectDataSourceに渡せるようにビジネスロジックを一時的にラップしてあげるといいかもしれない。

GridViewPage.cs

using System.Collections.Generic;

using System.ComponentModel.Composition;

using System.Web.UI.WebControls;
namespace Shumisen.Web.Form.IntegrationTest.Data

{

    public partial class GridViewPage : System.Web.UI.Page

    {

        [Import]

        public GridViewLogic GridViewLogic { private get; set; }
        protected void ObjectDataSource1_OnObjectCreating(object sender, ObjectDataSourceEventArgs e)

        {

            e.ObjectInstance = new LogicAdapter{ GridViewLogic = GridViewLogic};

        }
        public class LogicAdapter

        {

            private int _count;
            public GridViewLogic GridViewLogic { private get; set; }
            public IEnumerable<Book> GetBooks(int startRowIndex, int maximumRows)

            {

                return GridViewLogic.GetBooks(startRowIndex, maximumRows, out _count);

            }
            public int GetBookCount()

            {

                return _count;

            }

        }

    }

}

GridViewPage.cs.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="GridViewPage.aspx.cs" Inherits="Shumisen.Web.Form.IntegrationTest.Data.GridViewPage" %>



<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">

    <title></title>

</head>

<body>

    <form id="form1" runat="server">

    <div>

        <asp:GridView ID="GridView1" runat="server" AllowPaging="True" AllowSorting="true" AutoGenerateColumns="False"

            DataSourceID="ObjectDataSource1">

            <Columns>

                <asp:BoundField DataField="ASIN" HeaderText="ASIN" SortExpression="ASIN" />

                <asp:BoundField DataField="Title" HeaderText="Title" SortExpression="Title" />

            </Columns>

        </asp:GridView>

        

        <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="GetBooks"

            SelectCountMethod="GetBookCount" TypeName="Shumisen.Web.Form.IntegrationTest.Data.GridViewPage+LogicAdapter"

            EnablePaging="true" OnObjectCreating="ObjectDataSource1_OnObjectCreating" />

    </div>

    </form>

</body>

</html>

実行結果