When there’s a squiggly line in your code due to some error or warning, Visual Studio 2015 Preview provides an improved experience in dealing with them. When you hover over the squiggly line, aside from the fancy coloured tooltip, you’ll also get a link saying “Show potential fixes”:
Once you click on that “Show potential fixes”, you are given a list of actions. Note that you can also get to this list by clicking on the light bulb next to the tooltip, or else pressing Ctrl+. (read: Control Dot) on the keyboard while the caret is on the squiggly line.
When an item in the list is selected (but before you actually accept it), you get a handy preview (similar to what we saw with the unused usings) showing how the code will change as a result of that action. This means you will know what effect any fixes and refactoring (which will be covered in later articles) will have on your code before you take the plunge.