How can I make a windows application that doesn't have a square form shape?

I want to make an application that is similar to the World of warcraft launcher.

My main concern is to not have a square windows form with the typical close buttons, but a custom shape. How can I achieve this with C# and the .NET framew开发者_开发百科ork?

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Here's a tutorial on Creating Irregular Non-Rectangle Windows using WPF.

Consider this tutorial for creating Shaped Windows in WPF. It's got sample code in C#.

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There's a great piece of source code at http://www.codeproject.com/KB/GDI-plus/CsTranspTutorial3.aspx that allows you to make a form based off of any image with an alpha channel (like a .png), so that the transparent parts of the image correspond to places where you see through the form.