Bids4biz launch coming soon

We're getting closer to launch for bids4biz. I dont want to say a specific date right now but we do have a date set.

Dev has gone well, Ive been able to maximise code reuse without getting lost in abstraction. Theres a few other things I would like to implement like a "one click button user control" that uses javascript to disable the button after the first click and displays a throbber gif and perhaps even changes the button text to "Loading..." or "Please wait". Ill have to expose ValidationGroup, Text and the click event.

I still have a few issues with some of my user controls.

I have a UC which has a ModalPopup with login controls with validation. If I have multiple of these UC on the same page they fire each others validation which is not intended behaviour. Ive tried setting ValidationGroup to be unique (random generated string) on UC Init but still fires other instances validation. Will have to figure this one out soon.

Plinqo for bids4biz

We've been developing an exciting new website called Bids4biz.com.
I wont go into detail about the actual site yet (until we are closer to launch) but I will say a bit about my experience with PLINQO .

What is PLINQO?

Basically it's what LINQ to SQL should've been.
PLINQO is an ORM built on top of LINQ to SQL implemented as Codesmith templates so you'll need a copy of Codesmith to use it.

Why I chose PLINQO

Before I begun the project I had a few requirements in mind when deciding what framework to use for my business and data access layers:

• Code should be easily generated from Database schema
  
• Changes to my database schema should easily propagate to my code through code re-generation
• The code Generation tool should be simple to use
• Documentation should be readily available
• There should exist some implementation in the business layer objects to enforce business rules
• Performance should be good (for DB transactions)
• Objects should all have strongly typed properties.
• Should not be overly complex
• Learning curve not too steep

I looked at CSLA, nHibernate, Doodads, building from the ground up and of course PLINQO.
PLINQO by far fit my criteria above.

All I had to worry about was designing the DB then after specifying a few settings (with help from the video tutorials which were very easy to follow) then Codesmith generated all my classes and dbml from within Visual Studio.
If I make a change to my database, after 2-3 clicks, my code is updated to match.

I only needed to spend 30mins learning how it worked before I could jump right in and generate some code.


Development is still going and so is my learning experience with PLINQO but so far it has been an excellent choice.

[CompressionExtension] attribute with IIS compression

IIS has a feature that allows all outgoing responses to be compressed (usually zip). With content such as html and xml the benefit of doing this is much smaller packets back to the client since these types of documents can usually be compressed very well.
This may caus e you some issues when you are working with web services which are deployed on an IIS compression enabled server.
To get around this, you have to decompress the soap message before it gets consumed by your local proxy class.
There is an article here http://mastercsharp.com/article.aspx?ArticleID=86&TopicID=16 that explains the implementation and has the download.
What I needed to do in my project was import the reference to the above assembly and add the [CompressionExtension] attribute to every web service method on my proxy class.
The only annoyance is every time you update your web reference you have to re-add the using and all the attributes.
The good thing is I can now use IIS compression with my web services.

Designing a batch system with.net 2.0

A common requirement for larger scale systems is to have some kind of batch processing system. Batch processing is beneficial when you have certain tasks that consume alot of resources and the tasks are not urgent. An example might be sending out an email notification to subscribers or printing invoices.
There are a few things to keep in mind when designing a batch system:

• You should always use a sufficient amount of logging to help you resolve issues.
• Designing a good BatchJob base class will make things alot easier for future development.
• Batch system events should be visible.
• The Batch System should be easy to re-configure (dont hard code stuff you shouldnt).
• Build provisions for batch job failiures and time outs.
• Dispose of resources properly.

I'll write a bit about how I implemented a batch system I just finished using c#.net and an asp.net 2.0 application to provide visibilty of batch system events.

File upload manager Web User Control in ASP.net

Here is some code for a File upload manager control.
This control can:

• Upload multiple files


• Remove any uploaded files


• Check for duplicate uploads


• Reduces risk of concurrent file access issues by assigning a sessionId sub-folder under the upload directory.


• Remembers uploaded files over post backs.

All you have to do is assign the FileUploadDirectory property. This will be a full local path on the local machine.

Note. I have written this control with the intention of creating a re-usable dll, to see how to do this check my blog here: http://maoriitguy.blogspot.com/2008/07/creating-ascx-library.html

Create a new file in VS named FileUploadManager.ascx and paste this code:

<%@ Control Language="C#" ClassName="DKCS.FileUploadManager" %>
<script runat="server"> private string _fileUploadDirectory;
public ListItemCollection UploadFiles { get { return CheckBoxList1.Items; } }
public string Title { get { return Label1.Text; } set { Label1.Text = value; } }
public string FileUploadDirectory { get { return HiddenFieldUploadDir.Value; } set { if (!System.IO.Directory.Exists(value)) ThrowNotImplementedException();
_fileUploadDirectory = value + "/" + Session.SessionID;
try { System.IO.Directory.CreateDirectory(_fileUploadDirectory); } catch { ThrowNotImplementedException(); }
HiddenFieldUploadDir.Value = _fileUploadDirectory; } }
protected void Button2_Click(object sender, EventArgs e) { if (FileUpload1.FileName == null FileUpload1.FileName.Equals("")) return;
if (FileUploadDirectory == null FileUploadDirectory.Equals("")) { ThrowNotImplementedException(); }
//check File exists foreach (ListItem item in CheckBoxList1.Items) { if (item.Text.Equals(FileUpload1.FileName)) return; } string localFilePath = FileUploadDirectory + "/" + FileUpload1.FileName; FileUpload1.SaveAs(localFilePath);
CheckBoxList1.Items.Add(new ListItem(FileUpload1.FileName, localFilePath)); Button1.Enabled = true; }
private void ThrowNotImplementedException() { throw new NotImplementedException("The FileUploadManager.FileUploadDirectory property must be set to a absolute directory path on the local server. Ensure the asp.net application has permissions to read and write to the upload directory."); }
protected void Button1_Click(object sender, EventArgs e) { ListItemCollection temp = new ListItemCollection();
foreach (ListItem item in CheckBoxList1.Items) { if (item.Selected) { System.IO.File.Delete(item.Value); temp.Add(item); } }
foreach (ListItem item in temp) { CheckBoxList1.Items.Remove(item); }
if (CheckBoxList1.Items.Count == 0) { Button1.Enabled = false; } }
</script>
<div> <table> <tr> <td align="center" colspan="2"> <asp:Label ID="Label1" runat="server" Text="Upload Files"></asp:Label></td> </tr> <tr> <td> <asp:FileUpload ID="FileUpload1" runat="server" Width="300px" Height="24px" /></td> <td> <asp:Button ID="Button2" runat="server" Text="Upload" OnClick="Button2_Click" Width="80px" /></td> </tr> <tr> <td colspan="2"> <asp:CheckBoxList ID="CheckBoxList1" runat="server"> </asp:CheckBoxList> <asp:HiddenField ID="HiddenFieldUploadDir" runat="server" /> </td> </tr> <tr> <td align="center" colspan="2"> <asp:Button ID="Button1" runat="server" Text="Remove Selected" Enabled="False" OnClick="Button1_Click" /></td> </tr> </table></div>

Here is a screen of it inside a WebPartZone:

Creating an .ascx library in ASP.net

Here is a solution that will enable you to create .dlls for those useful re-usable web user controls you've created and use them in future asp.net web applications.

The msdn has a guide over here: http://msdn.microsoft.com/en-us/library/aa479318.aspx

lets assume you already have some web user controls in a asp.net website, if you dont, create some...
Heres how I got it to work:

1. For your .ascx control, embed your code behind into the page in a script block.
   <script runat="server">
   
   You will need to modify the Control tag, you should only use the Language and ClassName attributes. eg.
   <%@ Control Language="C#" ClassName="DKCS.FileUploadManager"%>
   Notice how I have prefixed the ClassName attribute with my namespace DKCS.
   
2. make sure the code compiles and test your control. Its a good idea to delete the code behind file if there was one being used previously.
   
3. Publish your website. The purpose of doing this is to generate the dlls for your controls.
   You will need to use these settings:
   -Deselect Allow this precompiled site to be updateable
   -Select Use fixed naming and single page assemblies
   -I also deselected enable strong naming on precompiled assemblies. This is useful if you want to put your control in the GAC.
   
4. Now browse to the location where you published your site to, look in the bin directory and you'll see some dll's in there. Your control will be named something like this:
   App_Web_fileuploadmanager.ascx.cdcab7d2.dll
   
   And there you have it, a dll with your control in it. It is actually a custom control but it has not lost any of its functionality as a web user control.
   

To use the dll:

1. Add a reference to the dll in your website.
2. On the page you want to use the control you will need to use the Register tag. Mine was configured like this:
   
   <%@ Register TagPrefix="DKCS" Namespace="DKCS" Assembly="App_Web_fileuploadmanager.ascx.cdcab7d2" %>
   
3. You should now be able to use your control on the page like this:
   
   
   
   The designer might not render it but it should be ok once you run it in a browser.