This working demonstrates an interesting and very useful concept in Entity Framework.
Introduction This working demonstrates an interesting and very useful concept in Entity Framework. Question: What is eager loading? In simple terms "when the loop is started, each of the objects that you have specified will be pulled from the database and built into a gigantic in-memory data structure. This will be a very expensive operation, pulling an enormous amount of data from your database. However, it will all happen in one database round trip, with a single SQL query execution". Step 1: Create a new web application Step 2: Adding a new Entity Data Model FrameworkStep 3: The complete code of WebForm1.aspx is as in the following: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="SelectDataEagerLoadingApp.WebForm1" %> <!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 id="Head1" runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <div> <center> <div> <table> <tr> <td colspan="2" align="center"> <asp:Label ID="Label1" runat="server" Text="Select Data - Eager Loading" Font-Bold="true" Font-Size="Large" Font-Names="Verdana" ForeColor="Maroon"></asp:Label></td> </tr> <tr> <td colspan="2" align="center"> <asp:Button ID="Button1" runat="server" Text="Select Data" Font-Names="Verdana" Width="213px" BackColor="Orange" Font-Bold="True" OnClick="Button1_Click" /></td> </tr> <tr> <td colspan="2" align="center"> <asp:GridView ID="GridView1" runat="server" CssClass="grid" BackColor="LightGoldenrodYellow" BorderColor="Tan" BorderWidth="1px" CellPadding="2" ForeColor="Black" GridLines="None"> <AlternatingRowStyle BackColor="PaleGoldenrod" /> <FooterStyle BackColor="Tan" /> <HeaderStyle BackColor="Tan" Font-Bold="True" /> <PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" HorizontalAlign="Center" /> <SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" /> <SortedAscendingCellStyle BackColor="#FAFAE7" /> <SortedAscendingHeaderStyle BackColor="#DAC09E" /> <SortedDescendingCellStyle BackColor="#E1DB9C" /> <SortedDescendingHeaderStyle BackColor="#C2A47B" /> <EmptyDataTemplate>No Records Found!</EmptyDataTemplate> </asp:GridView> </td> </tr> </table> </div> </center> </div> </form> </body> </html> Step 4: The complete code of WebForm1.aspx.cs is as in the following: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace SelectDataEagerLoadingApp { public partial class WebForm1 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs e) { using (CompanyEntities objEntities = new CompanyEntities()) { objEntities.ContextOptions.LazyLoadingEnabled = false; GridView1.DataSource = objEntities.tblEmployee.Take(15).ToList(); GridView1.DataBind(); } } } } Step 5: The output of the application is as in the following: Step 6: The select data output of the application is as in the following: I hope this working was useful for you. I look forward for your comments and feedback. Thanks Vijay.
Programming Dictionary in C#