Geek Daily

Here is what I liked this week. Enjoy!

Comparing Popular JavaScript/Ajax Frameworks
After four days of ASP.NET AJAX training with Stephen Walther I set out to learn more about my options in choosing a solution for a JavaScript/Ajax framework. If I realized days later I would be writing this comprehensive post on 7 of the most popular frameworks, I may have just went with the “Inny-Minny-Miney-Moe” method!

jQuery AJAX calls to a WCF REST Service
Since I’ve posted a few jQuery posts recently I’ve gotten a bunch of feedback to have more content on using jQuery in Ajax scenarios and showing some examples on how to use jQuery to cut out ASP.NET Ajax. In this post I’ll show how you can use jQuery to call a WCF REST service without requiring the ASP.NET AJAX ScriptManager and the client scripts that it loads by default. Note although I haven’t tried it recently the same approach should also work with ASMX style services.

SQL SERVER - Better Performance - LEFT JOIN or NOT IN?
First of all answer this question : Which method of T-SQL is better for performance LEFT JOIN or NOT IN when writing query? Answer is : It depends!

Video: Write Your First Silverlight Game
In this video, I demonstrate how to start writing your first Silverlight game. I show how to create a dramatic space scene, add a soundtrack, and associate movement with the mouse wheel. This is the first part of a two-part series.

Reading binary files using Ajax
But when it comes to binary files, helping hands from server-side technologies are often necessary.

So I googled around to see what I can do about binary files with Ajax and found this Marcus Granado’s post at http://mgran.blogspot.com/2006/08/downloading-binary-streams-with.html

What he posted there worked like a charm for FireFox and Safari but I couldn’t get it to work for IE.

But luckily, within the same page, someone had posted up a solution for IE as a comment, which is written in VBScript.

Safari CSS Masks
Webkit continues to impress with it’s early implementations of new standards. WebKit now supports alpha masks in CSS. Masks allow you to overlay the content of a box with a pattern that can be used to knock out portions of that box in the final display. In other words, you can clip to complex shapes based off the alpha of an image.

I talked about an issue I ran into between DateTime.MinValue and SqlDateTime.MinValue in a previous post. One other point I noticed while researching the topic was that, unlike almost all other types, SqlDateTime doesn’t have a TryParse method.

I really like the TryParse method because it helps me write code that is more terse and clean. I can easily use the TryParse methed as the condition for an if statement to handle the outcome without have to resort to ugly try catch blocks all over the place.

On Ian’s suggestion in the comments to my previous article I decided to take a stab at writing an extension method to implement this functionality. Now I said almost in the post title because I couldn’t get the TryParse method attached to the SqlDateTime native class. Now this could be due to this being my first attempt at an extension method so if anyone has any advice or suggestions on making this solution better feel free to leave them in the comments and I’ll update the code.

The solution

As I said I couldn’t get the method attached to the native type so this is the next best thing. I have declared a XSqlDateTime type that contains the TryParse method.

public static class XSqlDateTime {
	public static bool TryParse(string str, out SqlDateTime output) {
		try {
			output = SqlDateTime.Parse(str);
			return true;
		}
		catch {
			output = SqlDateTime.MinValue;
			return false;
		}
	}
}

This is easily used like so.

SqlDateTime date;
XSqlDateTime.TryParse("1/1/1953 12:00 AM", out date);

Just like all other implementations of TryParse on other types, if this method returns false it will assign the default type value to the output variable. In this case it is SqlDateTime.MinValue.

Hope this is useful to someone. I know it is for me. Cheers.