Zuker On Foundations

C# Lambda and Extensions to help around Casting

2008-10-07T05:33:00Z

One of the common scenarios of casting in daily use of code is the need to check if an instance is of a given type, if so - perform actions on it.

Some developers tend to do as following:

if (foo is Bar)
{
Bar b1 = (Bar)foo;
//Do Stuff..
}

A word about it - this approach is condered wasteful in this case.
This is because the result of whether the instance is of a 'Bar' type is not the only thing that matters in this case, meaning I still need to cast it and perform actions on it as 'Bar' type.

This is better in this case:

Bar b2 = foo as Bar;
if (b2 != null)
{
//Do Stuff
}

In this example, we first perform the cast, next we then simpy check if the casting succeeded.

I decided to write a small helper for this common thing.

Step 1 - Try Cast

public static bool TryCast<T>(object source, out T target) where T : class
{
target = source as T;
return (target != null);
}

//playing around - step 1
Bar b3;
if (Extensions.TryCast<Bar>(foo, out b3))
{
//Do stuff
}

Step 2 - Try Cast & Perform

public static void TryCastPerform<T>(object source, Action<T> action) where T : class
{
    T cast;
    if (TryCast<T>(source, out cast))
    {
        action(cast);
    }
}

//playing around - step 2
Extensions.TryCastPerform(foo,
    (Bar b4) =>
    {
   //Do Stuff
    });

Using Extensions:
Step 3 - Try Cast & Perform Extension

public static void TryCastPerformExt<T>(this object source, Action<T> action) where T : class
{
TryCastPerform<T>(source, action);
}

//playing around - step 3
foo.TryCastPerformExt((Bar b5) =>
{
//Do Stuff
});

Sample code is attached
In order to view the attached files, make sure you enter the specifc post page.

What is new in .NET 4.0?

2008-10-06T08:32:00Z

There's a whole buzz about the .NET Framework 4.0, sweet stuff is coming.

Read Damir's post for more information.

Obviously, this isn't everything..
- There will be new modeling and architecture tools for working against the code
- The Team Developer and Database suites will be combined together - Love that!
And much more of course

Dynamite: High Performace Dynamic Sorting Using Expressions

2008-10-02T06:32:00Z

Visit the CodeProject article for futher details.

Download Dynamite library (including demo) - 35.7KB

The library proides easy way for sorting arrays, enumerables, queryables and dataset as well.
The sweet gem about it is the ability to integrate it into actual runtime needs since it works with string manipulations.

Silverlight 2 RC is now available

2008-09-28T12:14:00Z

The RC version is out and ready for use.

Read Scott's post & Nicholas for what's out there.

Download Resources:

Visual Studio 2008 Tools RC0
Expression Blend SP1 RC0
Windows Silverlight 2 Dev Runtime RC0

SilverLight UI Resources

2008-09-18T07:28:00Z

Following are useful links to visit before writing a SilverLight application.

Some Silverlight effects libraries
SvLite Effects from Cellbi,
Silerlight.FX from Nikhil

Blacklight
Blacklight is a UX focused code sharing project. Microsoft has released a bunch of technologies that allow designers and developers to work closely together to make beautiful software. This project is a collection of controls, samples, visual assets and ideas that has been put together by User Experience designers and developers to both show you what the technology is capable of (from a UX point of view), and give you code and samples that you can use in your own projects, completely free of charge (see the License tab above). Check out the showcase to see what is currently available...

T-SQL - Create Unique Constraint

2008-09-10T04:44:00Z

Searched it for a while, thought it might be worth sharing.

Following is the T-SQL script to alter a table to apply a UNIQUE constraint on a certain column:

ALTER TABLE [TableName] WITH NOCHECK
ADD CONSTRAINT UniqueConstraintName UNIQUE ([ColumnName])

Custom Window Chrome in WPF

2008-09-10T04:25:00Z

Via this post.

"This document covers the design and some implementation details of getting WPF windows wrapped in custom chrome. Currently WPF supports standard windows, with an icon, title-text, and caption buttons, as well as borderless windows, which when combined with transparency allow arbitrary top-level shapes but the application loses system support for behaviors associated with having a standard caption area, such as maximize. There is a desire to create applications that fill a middle-ground here: the appearance and behavior of a standard window with a more complete branding experience"

Get the code here.

SQL 2005 - Save File into Image/VarBinary columns

2008-09-03T12:43:00Z

Via this post.

I created a column in a certain table to contain various files with "VarBinary(MAX)" as its data type.

I wanted to test stuff, so I needed data in the tables.

But Oh My, Now What? Should I really write C# Project to insert a file?

Well, no, not needed, you can do it directly from SQL.

Create Table EmployeeProfile
(
EmpId int,
EmpName varchar(50) not null,
EmpPhoto varbinary(max) not null
)
Go

Insert EmployeeProfile (EmpId, EmpName, EmpPhoto)
Select 1001, 'Vadivel',
BulkColumn from Openrowset( Bulk 'C:\Blue Lace 16.bmp', Single_Blob) as EmployeePicture

Execute code within timeout using threads

2008-08-21T06:20:00Z

Via this post.

Following is a quick way to execute code and limiting it within a certain timeout.

Note that the code spawns a new thread.
A better safer code would be using the ThreadPool and wait on the WaitHandle.

Thread t = new Thread(
   () =>
   {
      //Do Stuff Here
   });

   t.Start();

   bool success = t.Join(TimeSpan.FromSeconds(10));
   if (success)
   {
      //Thread completed successfully
   }
   else
   {
      throw new TimeoutException();
   }

PNG Transparency for IE6

2008-08-11T08:09:00Z

Internet Explorer 6 has problems displaying a PNG image with alpha transparency.

Follow the instructions detailed in this post to solve the issue.

Note that you should apply width & height for every image you apply the style to. (At least from my experience)

Hosting WCF Service in IIS w/ Windows Authentication

2008-08-10T11:00:00Z

I can't believe I wasted 10minutes on something that should be the simplest ever.

You might encounter an exception when trying to host a WCF service in IIS with windows authentication where it would say the IIS isn't configured with windows auth so the service itself can't be configured with windows auth.

I had that exception.

The problem is that the IIS vdir was configured with windows auth! and it still blew up.

After a quick searching, I found this post which did the trick.

So.. if you do encounter this, I hope I saved you some time.

LINQ to SQL Dynamic Mapping

2008-08-10T08:18:00Z

Via this post.

The post discusses the issue of using LINQ-to-SQL with dynamic mappings.

The problem
You have SQL Servers for each of your environments (development, test, pre-prod, production) and in each one, the table names are different. In fact, it’s not the table names that are different but the schema names but since the schema name is part of the table name, it must be specified.
Ex : dev.ZeTable et prod.ZeTable

Easy to solve, right? Just put the schema value in the config file and do a simple concatenation at runtime. Well, it’s not as easy as it seams because the table name is stored in an attribute of the partial class generated by the LINQ to SQL designer and Microsoft didn’t provide a way or method to change it at runtime.

[Table(Name="dev.ZeTable")]
public partial class TheTable

Solution
The solution is to dynamically load at runtime a mapping specific for each environment.
Here’s how to do it:. (Go to the post..)

Hosting WCF Service in IIS - 404 / Get Plain Text

2008-08-06T07:42:00Z

If you're trying to host a WCF service with a .svc extension and you get a 404 response or get plain text, it means your IIS had not been configured with the .svc extension.

Follow this post instructions.

IntelliSense for Expression Blend

2008-08-05T05:48:00Z

Via Stefan's post.

Wonderful News! You can enable intellisense in blend

You need to install a plug-in and there's a few gotcha's so do read Stefan's post for all the details.

A great discovery :)

Text Trimming Using CSS

2008-07-29T11:44:00Z

There is a non-so-familiar way to apply trimming to text in HTML using simple CSS.

In order to apply a certain width on an element and together ensure that its innerText will be bound to that and will be trimmed accordingly, we can do the following:

.LongTextContainer
{
   width: 300px;
   position: fixed;
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;
}

The text-overflow determines that the text will be trimmed while showing ellipsis in the end.

This seems to do the trick quite perfect.

Read additional information in this post.