I'm almost certain that you can't do this in .NET, and with good reason; blocks of code are not simply procedures like the VB6. .NET is full OOP programming, so you can not only have procedure definitions in classes (you should never use modules, since it defeats the purpose of .NET and OOP) you can have other classes, attributes on procedures, variable definitions scattered throughout the file, etc. Not only that, but it'd be must less productive.
You can use the #Region and #End Region directives to make portions of your code collapsable with a small title or description. This is great for keeping pieces of code separate without actually removing it from the code window.