Developer / Architect and not the other way around

Silverlight 3 Released!

2009-07-10T11:07:00.001-07:00

Check out the blog post from ScottGu:

Silverlight 3 Released
http://weblogs.asp.net/scottgu/archive/2009/07/10/silverlight-3-released.aspx

" is not a valid Win32 application. (Exception from HRESULT: 0x800700C1)"

2009-07-06T12:43:00.000-07:00

When working with IIS7 and Server 2008, and received this message: " is not a valid Win32 application. (Exception from HRESULT: 0x800700C1)"

The problem seems to be that the assemblies used to compile the website are 32 bit assemblies, and need to be "enabled" in the application pool.

Steps:
1. Open Internet Information Services IIS Manager
2. Select "Application Pools"
2. Locate the application pool for your web site
3. Choose "Advanced Settings..." for the application pool
4. Under the "(General)" section, set "Enable 32-Bit Applications" to True.

Problem fixed!

Firebug for Firefox

2009-03-24T13:13:00.000-07:00

Recently I've started using Firebug for development, and it's fast become one of my best tools as a web developer.

Firebug is a Firefox plug in what allows you to view, edit, and watch CSS, html and JavaScript on any page.

Resources:
http://getfirebug.com/

View Report Data window in Visual Studio 2008 / SRS 2008

2009-03-02T07:14:00.000-08:00

Recently when working with Visual Studio 2008 / Sql Reporting Services 2008, the enviroment crashed. When reopened, the "Report Data" window was missing.

To make the window display again, it's easy to find, but in a slighty different place than the usual (not under the "Other Windows" section). It is located on the View menu itself, in my case, the last option on the menu (see image below).

MSDN Southern Fried Roadshow - March 2009 Edition

2009-02-17T08:40:00.000-08:00

The MSDN Southern Fried Roadshow - March 2009 Edition has been announced and is open for registration.

From Glen Gordon on Pla.NET Southeast blog:
The MSDN Southern Fried Roadshow is a free developer event with a southern flair, where you will learn about some of the latest developments in Microsoft technologies. For March, 2009 the Roadshow will be presented by Architect Evangelist Chad Brooks and Developer Evangelists Glen Gordon and Brian Hitney. Chad, Glen & Brian will be loading up a minivan with lots of goodies, and trying to hit 4 cities in Mississippi, Alabama and Georgia in 4 days.

We're still working on nailing down the topics, check back in late January for the list.

We will also feature local speakers from each of our stops delivering short talks at the beginning of the Roadshow. These Homegrown Nuggets will sure be tasty!

Every attendee will receive a free MS Press book (while supplies last) as well as pointers to tons of resources for further learning.

Resources:
Registration: http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032403861&Culture=en-US

From Glen Gordon / Pla.NET Southeast blog

Atlanta Code Camp 2009 -- Save the date!

2009-02-10T10:58:00.000-08:00

Everyone-

If your interested, the 2009 Atlanta code camp is Saturday March 14th at the Georgia Gwinnet College located in Lawrenceville.

Interested in being a speaker at the event? You can sign up here. http://atlantacodecamp.com/calling-all-speakers/

Resources:
http://atlantacodecamp.com/

Business Intelligence

2009-01-26T06:54:00.000-08:00

This is a great primer presentation on Business Intelligence, and helps to dispel some of the common misconceptions about the area.

Lessons Learned in BI. View this recorded presentation by Aaron Erickson.

Resources:
Lessons Learned in BI
Magenic

Method not found: 'System.Object System.Windows.Threading.Dispatcher.Invoke

2009-01-19T17:49:00.000-08:00

When working with Microsoft Server 2008, and deploying an application, and after trying to run the first page:
"Method not found: 'System.Object System.Windows.Threading.Dispatcher.Invoke(System.Delegate, System.Object[])'."

The solution is simple: The server did not have Microsoft .Net Framework 3.1 SP 1 installed. After installing the package from here: Microsoft .NET Framework 3.5 Service Pack 1, everything was fixed.

Resources:
Microsoft .NET Framework 3.5 Service Pack 1

Other:
Here is the complete exception message from .net, in case anyone is searching for this fix using it
Method not found: 'System.Object System.Windows.Threading.Dispatcher.Invoke(System.Delegate, System.Object[])'.
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.MissingMethodException: Method not found: 'System.Object System.Windows.Threading.Dispatcher.Invoke(System.Delegate, System.Object[])'.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:
[MissingMethodException: Method not found: 'System.Object System.Windows.Threading.Dispatcher.Invoke(System.Delegate, System.Object[])'.]

Linq : Distinct and Case-Insensitive (StringComparer in action)

2009-01-09T08:35:00.000-08:00

Recently, working on a project, and ran into a simple problem. Wanted to get distinct entries from a List (but this solution will work with any class that uses IEnumerable)

Basically, the requirement needed to make the distinct collection of strings be not case sensitive, so : FileName1 was equal to filename1 or Filename1

Looking at the great Distinct extension method for link, it exposes an overload to specify IEqualityComparer comparer.

Rather than looking around, or thinking about writing something, check out the StringComparer class.

You can specify a StringComparer:
StringComparer CurrentCulture { get; }
StringComparer CurrentCultureIgnoreCase { get; }
StringComparer InvariantCulture { get; }
StringComparer InvariantCultureIgnoreCase { get; }
StringComparer Ordinal { get; }
StringComparer OrdinalIgnoreCase { get; }

Here is the result:
var results= fileList.Distinct(StringComparer.CurrentCultureIgnoreCase);

So simple, and easy to use!

Resources:
nested linq queries, how to get distinct values?

MSDTC partner transaction manager disabled

2009-01-05T12:13:00.000-08:00

"The partner transaction manager has disabled its support for remote/network transactions. (Exception from HRESULT: 0x8004D025)"

This message appears when MS DTC is not enabled for remote/network transactions. It would occur when trying to initiate a DTC controlled transaction involving more than one machine.

While DTC has been configured properly on the requesting machine, one of the remote respondant has not been configured to accept remote or network requests.

If you working with Vista, you can view my article on how to enable DTC on a Vista machine:Vista: MSDTC (DTC) and COM+ Configuration

Resources:
Vista: MSDTC (DTC) and COM+ Configuration

How Google Works...

2008-12-26T11:18:00.000-08:00

This is a great article on how Google's search engine works, and what specifically can cause it to reject/ignore your site:
http://www.googleguide.com/google_works.html

Resources:
How Google Works
Add your URL to Google

Csla 3.6 and Expert C# Business Objects 2008 Released...

2008-12-26T06:59:00.000-08:00

Version 3.6 of Csla .NET for Windows and Csla.NET for Silverlight have been released, and are available for download on Rockford Lhotka's website: http://www.lhotka.net/.

You can download the new versions of the framework from Lhotka.net, on the download page: http://www.lhotka.net/cslanet/download.aspx

The accompanying book is already available for purchase. You can get more information on the book, published by APress here: http://www.apress.com/book/view/9781430210191

This is the description of the book directly from APress:

Expert C# 2008 Business Objects
Do you want to create .NET applications that provide high performance and scalability? Do you want to employ object–oriented programming techniques in a distributed environment? Do you want to maximize the reuse and maintainability of your code? Then this book is for you.

In Rockford Lhotka’s Expert C# 2008 Business Objects, you’ll learn how to use advanced .NET Framework capabilities alongside OO design and programming to create scalable, maintainable object–oriented applications. Better still, this book includes CSLA .NET 3.6, a widely used framework on which you can base your application development. By using the concepts and framework in the book, you can focus more on your business issues and less on technology.

Using VS 2008 and C# 3.0, Rockford Lhotka shows you how CSLA .NET 3.6 allows great flexibility in object persistence, so business objects can use virtually any data sources available. The CSLA framework supports 1–, 2– and n–tier models through the concept of mobile objects. This provides the flexibility to optimize performance, scalability, security, and fault tolerance with no changes to code in the UI or business objects.

Business objects based on CSLA.NET 3.6 automatically gain many advanced features that simplify the creation of Windows forms, web forms, WPF, WCF, WF, and web services interfaces, and LINQ.

Resources:
APress
CSLA .NET 3.6 for Windows and for Silverlight is released!
Download

C# Collection Initializer

2008-12-24T06:45:00.000-08:00

A co-worker sent me this code change... nice.

Code to add items to a generic list:
_graphBackdrops = new List();

_graphBackdrops.Add(new Backdrop(Color.BlueViolet));
_graphBackdrops.Add(new Backdrop(Color.DarkSeaGreen));
_graphBackdrops.Add(new Backdrop(Color.DarkTurquoise));
_graphBackdrops.Add(new Backdrop(Color.Purple));
_graphBackdrops.Add(new Backdrop(Color.RoyalBlue));

Code to add items to a generic list, using a collection initializer:
_graphBackdrops = new List
{
new Backdrop(Color.BlueViolet),
new Backdrop(Color.DarkSeaGreen),
new Backdrop(Color.DarkTurquoise),
new Backdrop(Color.RoyalBlue)
};

-Thanks to Johannes!

If you want to take it a step further, you can also use object initalizers, like in this example from MSDN:
List cats = new List
{
new Cat(){ Name="Sylvester", Age=8 },
new Cat(){ Name="Whiskers", Age=2},
new Cat() { Name="Sasha", Age=14}
};

Note that you are setting the properties on the newly instantiated object, i.e. Name="Sylvester", Age=8

So rather than writing:
List cats = new List();
var cat = new Cat();
cat.Name = "Whiskers";
cat.Age = 2;
cats.Add(cat);

You can have:
List cats = new List
{new Cat(){ Name="Whiskers", Age=2}}

Much shorter, cleaner, and easier to maintain!

References:
Object and Collection Initializers (C# Programming Guide)
Anonymous Types (C# Programming Guide)

Convert DataTable to HtmlTable in c#

2008-12-23T09:07:00.000-08:00

After looking around for ten minutes, or so, and not finding a decent example if converting a System.Data.DataTable to System.Web.UI.HtmlControls.HtmlTable in c# (you can find some great examples of over-complexity and bad design), I wrote one.

This was not fun, it was easy. This is the most basic implementation I could come up with.

In the hopes of allowing someone else to avoid it, here is the code:

private HtmlTable ConvertToHtml(DataTable dataTable)
{
var htmlTable = new HtmlTable();
if (dataTable == null) return htmlTable; //null reference, empty table

HtmlTableRow htmlRow = new HtmlTableRow();
htmlTable.Rows.Add(htmlRow);

foreach (DataColumn column in dataTable.Columns)
htmlRow.Cells.Add(new HtmlTableCell(){InnerText=column.ColumnName});

foreach (DataRow row in dataTable.Rows)
{
htmlRow = new HtmlTableRow();
htmlTable.Rows.Add(htmlRow);

foreach(DataColumn column in dataTable.Columns)
htmlRow.Cells.Add(new HtmlTableCell(){InnerText=row[column].ToString()});
}

return htmlTable;
}

As a challenge, can you come up with a shorter way to write this code (or something more functionally complex? Here are some thoughts that I had:

1. WriteXml and use Xslt to translate to Html
2. WriteXml and then use LinqToXml to translate

Ideas? Post them.

Resources:
HtmlTable Class
System.Data.DataTable

SSRS ReportViewer "ASP.NET session has expired"

2008-12-22T09:13:00.000-08:00

When working with SSRS, after a idle person, if the user tries to run the report, or set parameter values, you might receive the message "ASP.NET session has expired"

There are a ton of posts out there, but very few solutions. What's worse, a few of the proposed solutions do not seem to work.

"ASP.NET session has expired."
1. ReportViewer AsyncRendering -- Quick fix?

First, you might want to configure your ReportViewer AsyncRendering rendering property to be set by a configuration file setting. It seems that setting AsyncRendering to false fixes the problem, but that might not be the greatest solution, but if you need to fix the problem immediately, you might try it. Additionally, if your trying to troubleshoot problems in your production enviroment, eliminating AsyncRendering for the ReportViewer is always a help.

More than one post seems to indicate that the AsyncRendering needs to be set to true if your web server name contains "_". No idea how true this is, but if you set AsyncRendering to false, and your images are missing, this might be your problem.

2. ReportViewer AutoRefresh

Since the ASP.NET session is expiring, you might try to set your reports to auto-refresh. In SSRS 2008, add the AutoRefresh element to your report.
Example:

<AutoRefresh>120</AutoRefresh>

Disclaimer: This is a work in progress. Both these solutions seem to work, but I am still looking for something better. If you find something, please add a comment and/or link. Thanks!

References:
Reports Render : ASP.NET session has expired
'ASP.NET session has expired' error in the ReportViewer control
Automatically refreshing your SQL Reporting Services reports with the AutoRefresh element

"type is not resolved for member" for Csla Security IPrincipal, IIdentity

2008-12-22T05:20:00.000-08:00

According to an article I found, when using the ASP.NET Development Server (VS Host or Cassini): ("Objects placed on the Thread object, such as the CurrentPrincipal, must be serializable and the assembly must be available to all AppDomains; even the primary AppDomain that isn’t running as part of your web site!"

Here is the article from Rockford Lhotka on the problem:
http://www.lhotka.net/WeBlog/CommentView,guid,cfcaf6c4-63cf-4cf1-8361-ed3db07496a4.aspx

To solve the problem, implement your own serialization for your IPrincipal and IIdentity objects:

//Identity class. Note: Inherits ISerializable

#region ISerializable Members

public void GetObjectData(SerializationInfo info, StreamingContext context)
{
//State will be CrossAppDomain for serialization induced by WebDev.WebServer
if(context.State.Equals(StreamingContextStates.CrossAppDomain))
{
var generic = new GenericIdentity(this.Name, this.AuthenticationType);

info.SetType(generic.GetType());

var serializableMembers = FormatterServices.GetSerializableMembers(generic.GetType());
var serializableValues = FormatterServices.GetObjectData(generic, serializableMembers);

for(int i = 0; i < serializableMembers.Length; i++)
info.AddValue(serializableMembers[i].Name, serializableValues[i]);
}
else
throw new InvalidOperationException("Serialization not supported");
}

#endregion

//Principal class. Note: Inherits ISerializable
#region ISerializable Members

public void GetObjectData(SerializationInfo info, StreamingContext context)
{
//State will be CrossAppDomain for serialization induced by WebDev.WebServer
if (context.State.Equals(StreamingContextStates.CrossAppDomain))
{
var identity = (MyIdentity)this.Identity;

var generic = new GenericPrincipal(identity, identity.Roles.ToArray()); ;

info.SetType(generic.GetType());

var serializableMembers = FormatterServices.GetSerializableMembers(generic.GetType());
var serializableValues = FormatterServices.GetObjectData(generic, serializableMembers);

for (int i = 0; i < serializableMembers.Length; i++)
info.AddValue(serializableMembers[i].Name, serializableValues[i]);
}
else
{
throw new InvalidOperationException("Serialization not supported");
}
}

#endregion

Things to do to make this work:
1. ISerializable on both IPrincipal, IIdentity
2. Added property to expose roles on identity object for IPrincipal serialization

This is a minor problem, and the fix above works like a charm. The hardest part was finding the solution. Thanks to Rocky...

Resources:
Update on my struggles with the ASP.NET Development Server
Type is not resolved for member ... Having problems enabling debugging

Execute client side script in IFrame from parent page

2008-12-12T09:13:00.000-08:00

To execute a script within in IFRAME from the parent page

Seems simple right? Sure it is... unless you want something that works in IE, Firefox, Chrome, and Safari. There are tons of blog posts, and articles on how to execute the script from the IFRAME on the parent, but surprisingly few articles on the opposite.

At the end of the day, this code should work in all 4 browsers:
function fnEvalFrame(iframe, command) {
if (!iframe.eval && iframe.execScript) {
iframe.execScript("null");
}
iframe.eval(command);
}

Also, when referring to your frames, use self.frames (or self.frames[], window.frames[], top.frames[], parent.frames[]) and not document.frames

References:
Firefox and document.frames
SSRS And Firefox
JavaScript eval in iframes

Exceptions

2008-11-20T05:47:00.000-08:00

One of my pet peeves is a developer not implementing exception handling in a useful manner. Exception handling needs to be an important part of design and not just wrapping all your code in a try/catch block. This does nothing for me:

catch (Exception ex)
{
    [Do something]
}

even worse is this:

catch (Exception ex)
{
    [Do something]
    throw ex;
}

All this does is give away the full stack trace for any exception handling further up the chain.

A better pattern/design/practice for handling exceptions would be to actually handle any exceptions you're catching. That means catching specific exceptions like InvalidOperationException, ArgumentException , or even better, a custom, meaningful exception specific to the task instead of the base Exception.

Speaking of custom, if you're going to define your own exceptions, be sure to provide grammatically correct messages that will be meaningful to someone down the road. Also include the three common constructors that are implemented by all the system exceptions (No parameters, single string parameter, and string parameter and inner exception parameter).

When throwing exceptions, use care to choose the correct type instead of just throwing ApplicationException. Consider returning null for cases of extremely common errors instead of throwing an exception. And most importantly, don't use exceptions as part of normal program flow. Remember try/catch is analogous to a goto statement so don't abuse it.

Resources:
http://msdn.microsoft.com/en-us/library/seyhszts.aspx

Deep Zoom as a Code Visualizer

2008-11-13T09:49:00.000-08:00

One of the cooler pieces of Silverlight 2 is the Deep Zoom Composer which allows an easy way to display high-resolution images. The ubiquitous Hard Rock Memorabilia site is an excellent example of its use. As its adoption grows, other, more interesting, applications have been developed. One really good one is Zoomery, which is using the technology as a code visualizer. The ability to quickly scan through the class diagrams and embedding notes directly within them is brilliant.

Oftentimes, Silverlight gets a bad rap as a Flash clone but this innovation illustrates (quite literally) it can be very original as well. I hope it continues to get Microsoft and third-party development and support.

Using Reflection to Instantiate a Generic Type

2008-11-12T10:36:00.000-08:00

How to use Activator.CreateInstance to instantiate a generic type based on a name and type parameters? It's not quite as simple as I thought. First mark the fully qualified name of the class by appending a backquote (`) and the number of type arguments. Then you can do make the type generic by calling the MakeGenericType method and passing in the types.

string generic = string.Format("{0}`{1}", _className, _genericTypeParams.Count);
Type genericType = Type.GetType(generic).MakeGenericType(_genericTypeParams.ToArray());

x = Activator.CreateInstance(genericType);

Voila

C# 4.0 Features Announced!

2008-11-11T04:36:00.000-08:00

Check out Dave Morton's post on C# 4.0 Features Announced!

You can also view the information directly at Microsoft : http://code.msdn.microsoft.com/csharpfuture

Resources:
http://code.msdn.microsoft.com/csharpfuture

Sql Management Studio : Prevent saving changes that require the table to be recreated

2008-11-11T04:27:00.000-08:00

When working with the table designer in Microsoft Sql Server Management Studio 2008, I tried to save a table I modified, and received this message:
Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can't be recreated or enabled the option Prevent saving changes that require the table to be re-created.

Enabling the option to allow you to complete these types of actions is pretty easy, from the "Options" menu, select the "Designers" tab, and the uncheck the "Prevent saving changes that require table re-creation". Then click "OK"

Problem solved. Hey Microsoft: It would be great if this feature would allow for three levels: On, Off, and Warn.

SQL Server Reporting Services 2008 on Vista : "RsClientController is undefined"

2008-11-06T18:48:00.000-08:00

When working with the Sql Server 2008 Reporting Services web control on a Vista workstation, I was receiving a JavaScript error message: "RsClientController is undefined".

First, I thought to check the Handler Mappings, since I've experienced a similar problem with the .axd extension not being mapped properly. No luck. The mapping existed, and was set properly.

After investigating, and digging into the problem a little deeper, it would seem the solution is to add a mapping specifically for the Reserved.ReportViewerWebControl.axd

These are the steps:
1. Open Internet Information Services (IIS Manager)
2. Select your reporting site
3. Click on the "Add Managed Handler" from the actions

4. Enter the information for your new handler:

5. Click 'OK'

Resources:
Deployed reports have javascript errors?
Javascript Error When trying url access
SQL Server Web Report Viewer Issues on Longhorn/IIS7

"Microsoft.CSharp.targets" was not found

2008-10-31T08:33:00.000-07:00

While working with a manually merged project file and attempting to complete the upgrade from Visual Studio 2005 to 2008 the conversion process failed.

After the conversion failure, Visual Studio became unresponsive, and the build for the solution failed. To resolve the problem, I attempted to unload and reload the solution.

When loading the message appeared: "C:\Windows\Microsoft.NET\Framework\v3.5\Microsoft.CSharp.targets" was not found."

A quick check found that the target build file for C# had been removed from the framework folder, without the build definition file for C#, projects cannot seem to reload (let alone build correctly).

To resolve the problem, I copied the file from another machine into the folder, and reloaded the solution.

Problem solved.

Resources:
MSBuild .Targets Files
TFS Build Problem - Custom Property not getting passed to recursive imports.

MOSS: Access is denied. Check that the Default Content Access Account has access to this content, or add a crawl rule to crawl this content.

2008-10-27T07:26:00.000-07:00

When working with MOSS today: Running a farm setup on a single machine with Server 2008, Sql Server 2008, and MOSS 2007.

Trying to get the search service to complete a Crawl of the local SharePoint sites, I was receiving "Access is denied. Check that the Default Content Access Account has access to this content, or add a crawl rule to crawl this content."

After validating that the account had access to the content (sites), and verifying that there were no crawl rules, I eventually expected to find the answer in the event log.

In the event log, there were no entries like the expected "Login failed for user 'NT AUTHORITY\NETWORK SERVICE'. [CLIENT: ]", and according to the log everything was running correctly.

As an additional check, I set up the crawler service to run against another SharePoint server, using the same crawl account credentials. Worked fine without a problem.

After checking around, I ran across this post on Microsoft TechNet Forums: http://social.technet.microsoft.com/forums/en-US/sharepointsearch/thread/84f93fbe-f4a6-4683-b25b-b595b9006ad7/

Within the post, someone recommends re-entering the crawler account credentials. I re-entered the credentials, and initiated a full site crawl. The error still occurred, with the same message.

After reading further into others that had encountered this problem, it would appear that the Loopback check security feature is back in Server 2008. After running the work-around http://support.microsoft.com/kb/896861 (see Method 1: Disable the loopback check), and restarting the machine the site can now be crawled.

Resources:
http://social.technet.microsoft.com/forums/en-US/sharepointsearch/thread/84f93fbe-f4a6-4683-b25b-b595b9006ad7/
http://support.microsoft.com/kb/896861