Back in August 2007, Microsoft released a critical update for a Visual Basic 6 Runtime file. The file, OLEAUT32.DLL, contains a vulnerability that can be exploited and allowing an attacker to gain complete control of a computer if the logged-on user has Administrator privileges. The exploit may be performed by a COM component or an ActiveX control residing in a Windows application or a Web page.

The vulnerability itself is caused by the improper checking of input data, allowing specially crafted memory requests to be passed to the Windows OLE Automation service. The OLEAUT32.DLL library provides the API to COM and ActiveX components to access this service. The update released by Microsoft patches the vulnerability by adding validity checking to memory requests.

So what’s to worry? You faithfully run Microsoft Update on the second Tuesday of every month, right? Well, hang on to your mouse–not all critical updates released by Microsoft are distributed through Microsoft Updates. This Visual Basic critical vulnerability is one that you’ll need to patch yourself.

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Exam objective: 70-526 - Configure the PropertyGrid component

The .NET Framework contains a fairly complete selection of controls and form components that allow information to be input, presented and changed in many different ways. In this article I will cover one of the more complex but also feature-rich components in the .NET framework: the PropertyGrid. Regardless of whether you have experience with the using the PropertyGrid in your own apps, if you used Visual Studio, you already used the PropertyGrid component many times. Visual Studio uses several PropertyGrid components in its main interface, the most obvious being the Properties and Events windows, highlighted in the screenshot below:

So setting the Properties of a Form or control for example is done by using a PropertyGrid and as you can see, it is very complete. It allows you to set a wide variety of Property types such as Booleans, Strings, Integers, Fonts, Point and Size structures, Colors, Images, Enums, and Collections without the need for complex code. Additionally, the PropertyGrid component can be extended to support additional custom property types and to customize the GUI of the properties in the PropertyGrid.

The PropertyGrid is particularly useful when you have a good amount of different properties that need to be set or displayed in the proper format. If you would use a combination of labels, textboxes, radio buttons, checkboxes, etc. you would have to create many different controls and write input validation code. That doesn’t mean a PropertyGrid is always a better alternative, a form with the classic form components works best for most applications as users are familiar with it.

Throughout the rest of this article we’re going to create an example project that shows you how little effort it takes to add a working PropertyGrid to a Form. After going over some basic properties of the PropertyGrid itself, we’ll cover its implementation in more detail. I assume you have some basic experience with Visual Studio and setting control properties using the GUI.

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Covers Exam Objective: 70-526 - Create and configure a MenuStrip component on a Windows Form.

One of the challenges with designing graphical user interfaces is to present the controls and information when the user needs them and at the same time not clutter the interface. Most applications however, include a wide variety of options and functions that need to be within reach at all times. A familiar way to allow users access to common functions in Windows applications is to use menus.

There are many different types of menus being used in today’s software of which several are available as components in the .NET framework. By creating custom controls, extending existing controls, and/or by using GDI+, you can create an endless range of menus that differ in look and functionality. In this article, I will cover the two exam objectives listed above, so in particular the MenuStrip component.

The MenuStrip represents the most common menus in Windows apps – the main menu at the top that often starts with a File menu option. It is derived from the ToolStrip component. Just to make sure we all know up front what we’re talking about, the following image depicts the menu in Visual Studio VB Express edition:

As we all know, most of Microsoft’s own software often includes a huge amount of menu options. There is a good chance the first app(s) you create do not contain that many options and then a MenuStrip may seem like overkill. However, besides being a familiar component for users, it can give the GUI some weight and it can easily be extended because of its hierarchical structure. So if the functionality of your application is likely to expand over time, using a MenuStrip from the start can prevent you from having to make major changes to the GUI.

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Microsoft Certification Exam: 70-526 (MCTS)
Objective: Create and use custom dialog boxes in Windows Forms applications.
Language: Visual Basic 2005 (click here for the C# version of this entry)

I remember the first time I needed to create a dialog box in a .NET application that I was writing in C#. Being a long-time Visual Basic programmer, I assumed that this could easily be accomplished by using a dialog box template included with Visual Studio.NET. To my surprise, no such form template existed for C#, although one does for Visual Basic 2005. After wading through several books and Web pages filled with information on Windows Forms 2.0 programming, a basic set of steps became apparent to me for manually converting a .NET form into a Windows dialog box:

1. Add a Form to your .NET project and name it “DialogBoxForm”.

2. Drop two buttons in the lower right-hand area of the Form and name them “OKButton” and “CancelButton”.

3. Change the following properties of the Form to adjust its appearance and behavior to be like a standard dialog box: (more…)