Hi Imar,

When I try to view NewPhotoAlbum.aspx getting following error

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:


Line 17:
Line 18: PhotoAlbum myPhotoAlbum = (PhotoAlbum)e.Entity;
Line 19: Response.Redirect(string.Format("ManagePhotoAlbum. aspx?PhotoAlbumId={0}", myPhotoAlbum.Id.ToString()));
Line 20: }
Line 21: }

I verified my code with the downloaded code there is no difference

Also done debugging it says myPhotoAlbum is null

Dont know how to fix it.

My NewPhotoAlbum.aspx is

<%@ Page Title="Create New Photo Album" Language="C#" MasterPageFile="~/MasterPages/Frontend.master" AutoEventWireup="true" CodeFile="NewPhotoAlbum.aspx.cs" Inherits="_NewPhotoAlbum" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="cpMainContent" runat="Server">
<asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False" DataKeyNames="Id" DataSourceID="EntityDataSource1" DefaultMode="Insert" Height="50px" Width="125px">
<Fields>
<asp:BoundField DataField="Id" HeaderText="Id" ReadOnly="True" SortExpression="Id" InsertVisible="False" />
<asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
<asp:CommandField ShowInsertButton="True" />
</Fields>
</asp:DetailsView>
<asp:EntityDataSource ID="EntityDataSource1" runat="server" ConnectionString="name=PlanetWroxEntities" DefaultContainerName="PlanetWroxEntities" EnableFlattening="False" EnableInsert="True" EntitySetName="PhotoAlbums" OnInserted="EntityDataSource1_Inserted">
</asp:EntityDataSource>
</asp:Content>
My NewPhotoAlbum.aspx.cs is

public partial class _NewPhotoAlbum : BasePage
{
protected void Page_Load(object sender, EventArgs e)
{

}

protected void EntityDataSource1_Inserted(object sender, EntityDataSourceChangedEventArgs e)
{

PhotoAlbum myPhotoAlbum = (PhotoAlbum)e.Entity;
Response.Redirect(string.Format("ManagePhotoAlbum. aspx?PhotoAlbumId={0}", myPhotoAlbum.Id.ToString()));
}
}

Pl. help me fix the code.

Mary Sunish

Hi there,

Are you sure all Id columns in the database are primary key *and* an Identity? If not, fix them in the database and then recreate the EF model. You can find more info here: Cannot redirect to ManagePhotoAlbum (targets the 3.5 book with LINQ to SQL instead of EF but the principle is the same).

Cheers,

Imar

__________________
Imar Spaanjaars
http://Imar.Spaanjaars.Com
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Author of Beginning ASP.NET 4.5 : in C# and VB, Beginning ASP.NET Web Pages with WebMatrix
and Beginning ASP.NET 4 : in C# and VB.
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I copied your mdf file to mine and it works now.

Thanks

Mary Sunish