Chapter 13,page 462

Masego.Moikanyang · March 19th, 2011, 01:57 PM

HI

I'm currently experiencing this problem.The application executes well but it throws me back in the debugger as it shows me this message:Object reference not set to an instance of an object.Any way around this?

Imar · March 19th, 2011, 02:16 PM

Hi there,

Can you post the code for the pages NewPhotoAlbum.aspx and ManagePhotoAlbum.aspx and the code behind of these pages? Please paste the code in Notepad first, then copy and paste it here and use the Code formatting button (#) on the toolbar. Otherwise, this forum messes up your code ;-(

Cheers,

Imar

Masego.Moikanyang · March 19th, 2011, 02:48 PM

Here they are:
ManagePhotoAlbum.aspx
<asp:ListView ID="ListView1" runat="server" DataKeyNames="Id"
DataSourceID="LinqDataSource1" InsertItemPosition="LastItem"
oniteminserting="ListView1_ItemInserting">
<ItemTemplate>
<li style="">
Description:
<asp:Label ID="DescriptionLabel" runat="server"
Text='<%# Eval("Description") %>' />
 
Tooltip:
<asp:Label ID="TooltipLabel" runat="server" Text='<%# Eval("Tooltip") %>' />
 
<asp:Image ID="ImageUrl" runat="server" ImageUrl='<%# Eval ("ImageUrl") %>' />
 
<asp:Button ID="DeleteButton" runat="server" CommandName="Delete"
Text="Delete" CausesValidation="false" />
</li>
</ItemTemplate>
<InsertItemTemplate>
<li style="">
Description:
<asp:TextBox ID="DescriptionTextBox" runat="server" TextMode="MultiLine"
Text='<%# Bind("Description") %>' />
 
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" ControlToValidate="DescriptionTextBox" runat="server" ErrorMessage="Please enter a description"></asp:RequiredFieldValidator>
Tooltip:
<asp:TextBox ID="TooltipTextBox" runat="server" Text='<%# Bind("Tooltip") %>' />
 
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" ControlToValidate="ToolTipTextBox" runat="server" ErrorMessage="Please enter a tooltip"></asp:RequiredFieldValidator>
<asp:FileUpload ID="FileUpload1" runat="server" /> 
<asp:CustomValidator ID="CustomValidator1" runat="server" ErrorMessage="Please select a valid .jpg file"></asp:CustomValidator>
<asp:Button ID="InsertButton" runat="server" CommandName="Insert"
Text="Insert" />
<asp:Button ID="CancelButton" runat="server" CommandName="Cancel"
Text="Clear" CausesValidation="false" />
</li>
</InsertItemTemplate>
<LayoutTemplate>
<ul class="itemContainer">
<li ID="itemPlaceholder" runat="server" />
</ul>
</LayoutTemplate>
</asp:ListView>
<asp:LinqDataSource ID="LinqDataSource1" runat="server"
ContextTypeName="Cell_WareDataContext" EnableDelete="True" EnableInsert="True"
TableName="Pictures" Where="PhotoAlbumId == @PhotoAlbumId"
oninserting="LinqDataSource1_Inserting">
<WhereParameters>
<asp:QueryStringParameter DefaultValue="-1" Name="PhotoAlbumId"
QueryStringField="PhotoAlbumId" Type="Int32" />
</WhereParameters>
</asp:LinqDataSource>
Code-Behind of ManagePhotoAlbum.aspx
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

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

}
protected void LinqDataSource1_Inserting(object sender, LinqDataSourceInsertEventArgs e)
{
Picture myPicture = (Picture)e.NewObject;
myPicture.PhotoAlbumId = Convert.ToInt32(Request.QueryString.Get("PhotoAlbu mId"));

FileUpload FileUpload1 = (FileUpload)ListView1.InsertItem.FindControl("File Upload1");
string virtualFolder = "~/Cell-Pics/";
string physicalFolder = Server.MapPath(virtualFolder);
string filename = Guid.NewGuid().ToString();
string extension = System.IO.Path.GetExtension(FileUpload1.FileName);

FileUpload1.SaveAs(System.IO.Path.Combine(physical Folder, filename + extension));
myPicture.ImageUrl = virtualFolder + filename + extension;
}
protected void ListView1_ItemInserting(object sender, ListViewInsertEventArgs e)
{
FileUpload FileUpload1 = (FileUpload)ListView1.InsertItem.FindControl("Find Upload1");
if (!FileUpload1.HasFile || !FileUpload1.FileName.ToLower().EndsWith(".jpg"))
{
CustomValidator CustomValidator1 =
(CustomValidator)ListView1.InsertItem.FindControl( "CustomValidator1");
CustomValidator1.IsValid = false;
e.Cancel = true;
}
}
}

NewPhotoAlbum.aspx
<asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False"
DataKeyNames="Id" DataSourceID="LinqDataSource1" DefaultMode="Insert"
Height="50px" Width="125px">
<Fields>
<asp:BoundField DataField="Id" HeaderText="Id" ReadOnly="True"
SortExpression="Id" />
<asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
<asp:CommandField ShowInsertButton="True" />
</Fields>
</asp:DetailsView>
<asp:LinqDataSource ID="LinqDataSource1" runat="server"
ContextTypeName="Cell_WareDataContext" EnableInsert="True"
oninserted="LinqDataSource1_Inserted" TableName="PhotoAlbums">
</asp:LinqDataSource>

CodeBehind of NewPhotoAlbum.aspx
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

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

}
protected void LinqDataSource1_Inserted(object sender, LinqDataSourceStatusEventArgs e)
{
PhotoAlbum myPhotoAlbum = (PhotoAlbum)e.Result;
Response.Redirect(string.Format("ManagePhotoAlbum. aspx?PhotoAlbumId={0}", myPhotoAlbum.Id.ToString()));
}
}

Masego.Moikanyang · March 19th, 2011, 03:19 PM

Here they are:
ManagePhotoAlbum.aspx
<asp:ListView ID="ListView1" runat="server" DataKeyNames="Id"
DataSourceID="LinqDataSource1" InsertItemPosition="LastItem"
oniteminserting="ListView1_ItemInserting">
<ItemTemplate>
<li style="">
Description:
<asp:Label ID="DescriptionLabel" runat="server"
Text='<%# Eval("Description") %>' />
 
Tooltip:
<asp:Label ID="TooltipLabel" runat="server" Text='<%# Eval("Tooltip") %>' />
 
<asp:Image ID="ImageUrl" runat="server" ImageUrl='<%# Eval ("ImageUrl") %>' />
 
<asp:Button ID="DeleteButton" runat="server" CommandName="Delete"
Text="Delete" CausesValidation="false" />
</li>
</ItemTemplate>
<InsertItemTemplate>
<li style="">
Description:
<asp:TextBox ID="DescriptionTextBox" runat="server" TextMode="MultiLine"
Text='<%# Bind("Description") %>' />
 
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" ControlToValidate="DescriptionTextBox" runat="server" ErrorMessage="Please enter a description"></asp:RequiredFieldValidator>
Tooltip:
<asp:TextBox ID="TooltipTextBox" runat="server" Text='<%# Bind("Tooltip") %>' />
 
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" ControlToValidate="ToolTipTextBox" runat="server" ErrorMessage="Please enter a tooltip"></asp:RequiredFieldValidator>
<asp:FileUpload ID="FileUpload1" runat="server" /> 
<asp:CustomValidator ID="CustomValidator1" runat="server" ErrorMessage="Please select a valid .jpg file"></asp:CustomValidator>
<asp:Button ID="InsertButton" runat="server" CommandName="Insert"
Text="Insert" />
<asp:Button ID="CancelButton" runat="server" CommandName="Cancel"
Text="Clear" CausesValidation="false" />
</li>
</InsertItemTemplate>
<LayoutTemplate>
<ul class="itemContainer">
<li ID="itemPlaceholder" runat="server" />
</ul>
</LayoutTemplate>
</asp:ListView>
<asp:LinqDataSource ID="LinqDataSource1" runat="server"
ContextTypeName="Cell_WareDataContext" EnableDelete="True" EnableInsert="True"
TableName="Pictures" Where="PhotoAlbumId == @PhotoAlbumId"
oninserting="LinqDataSource1_Inserting">
<WhereParameters>
<asp:QueryStringParameter DefaultValue="-1" Name="PhotoAlbumId"
QueryStringField="PhotoAlbumId" Type="Int32" />
</WhereParameters>
</asp:LinqDataSource>
Code-Behind of ManagePhotoAlbum.aspx
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

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

}
protected void LinqDataSource1_Inserting(object sender, LinqDataSourceInsertEventArgs e)
{
Picture myPicture = (Picture)e.NewObject;
myPicture.PhotoAlbumId = Convert.ToInt32(Request.QueryString.Get("PhotoAlbu mId"));

FileUpload FileUpload1 = (FileUpload)ListView1.InsertItem.FindControl("File Upload1");
string virtualFolder = "~/Cell-Pics/";
string physicalFolder = Server.MapPath(virtualFolder);
string filename = Guid.NewGuid().ToString();
string extension = System.IO.Path.GetExtension(FileUpload1.FileName);

FileUpload1.SaveAs(System.IO.Path.Combine(physical Folder, filename + extension));
myPicture.ImageUrl = virtualFolder + filename + extension;
}
protected void ListView1_ItemInserting(object sender, ListViewInsertEventArgs e)
{
FileUpload FileUpload1 = (FileUpload)ListView1.InsertItem.FindControl("Find Upload1");
if (!FileUpload1.HasFile || !FileUpload1.FileName.ToLower().EndsWith(".jpg"))
{
CustomValidator CustomValidator1 =
(CustomValidator)ListView1.InsertItem.FindControl( "CustomValidator1");
CustomValidator1.IsValid = false;
e.Cancel = true;
}
}
}

NewPhotoAlbum.aspx
<asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False"
DataKeyNames="Id" DataSourceID="LinqDataSource1" DefaultMode="Insert"
Height="50px" Width="125px">
<Fields>
<asp:BoundField DataField="Id" HeaderText="Id" ReadOnly="True"
SortExpression="Id" />
<asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
<asp:CommandField ShowInsertButton="True" />
</Fields>
</asp:DetailsView>
<asp:LinqDataSource ID="LinqDataSource1" runat="server"
ContextTypeName="Cell_WareDataContext" EnableInsert="True"
oninserted="LinqDataSource1_Inserted" TableName="PhotoAlbums">
</asp:LinqDataSource>

CodeBehind of NewPhotoAlbum.aspx
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

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

}
protected void LinqDataSource1_Inserted(object sender, LinqDataSourceStatusEventArgs e)
{
PhotoAlbum myPhotoAlbum = (PhotoAlbum)e.Result;
Response.Redirect(string.Format("ManagePhotoAlbum. aspx?PhotoAlbumId={0}", myPhotoAlbum.Id.ToString()));
}
}

Imar · March 20th, 2011, 08:08 AM

Hi there,

When you post code in the future, can you please follow my advise and wrap the code in code tags use the Code button (#) on the toolbar? Your current code is hard to read, and contains a number of issues / errors due to a formatting bug in this fourm (extra spaces get added for example).

Anyway, I think the problem is in this code:

Code:

 
FileUpload FileUpload1 = (FileUpload)ListView1.InsertItem.FindControl("FindUpload1");

The control is called FileUpload1, not FindUpload1.

Cheers,

Imar

Masego.Moikanyang · March 21st, 2011, 08:42 AM

Code:

Yes thanks for that information.Anyway regarding the project this line of code:FileUpload1.SaveAs(System.IO.Path.Combine(physicalFolder, filename + extension));
generates this exception:Could not find a part of the path 'C:\Users\Masego\Documents\Visual Studio 2008\WebSites\Cell-Ware\Cell-Pics\fa6466b0-b14d-4100-aa3d-2c3e77abfc35.jpg'.When there are already pics in the folder,what could be the problem?

Imar · March 21st, 2011, 08:47 AM

It could be a permissions issue. Does the site run under IIS? If so, it doesn't have access to your User folder. That's the reason the site is placed in a folder such as C:\BegASPNET. Obviously, other locations like C:\Inetpub should work as well, as long as the IIS account has access.

Cheers,

Imar

Masego.Moikanyang · March 21st, 2011, 09:40 AM

Code:

Ok.How do go about checking if it does run on an IIS?

Imar · March 21st, 2011, 09:43 AM

What do you see in the browser's Address bar? And how did you set up and start the site?

Either way, it's probably a good idea to move the site out of your Documents folder, and configure security settings as explained in the book.

Cheers,

Imar

Masego.Moikanyang · March 22nd, 2011, 02:34 PM

Well this is what I see in the address bar:http://localhost:56805/Cell-Ware/Man...toAlbum.aspx.I set up the site according to the book chapter 2 page 37 unless I did something otherwise.