Keeping Debugging Data on the Screen
I admit it: I don't use the Watch window much. When I hit a breakpoint and want to know what the current value is in a variable that's near the breakpoint, I'll either type "?variableName" in the Immediate window or hover my mouse over the variable to have Visual Studio pop up a Data Tip with the variable name and value.
If you're a "hover your mouse" kind of person you should pay attention to the pushpin at the end of the Data Tip: If you click on the pushpin and switch it to the "upright" position, that Data Tip will stay on the screen. The next time you hit the breakpoint (actually, whenever you have that part of your code on the screen) the Data Tip will be there, displaying the current value of the variable. If you need to drill down into the variable, you can use the plus sign (+) at the beginning of the Data Tip to see the values on the item's properties.
You can do more with your Data Tip: When you hover your mouse over the Data Tip, a "mini-menu" of choices will appear just past the end of the Data Tip. The middle icon in this mini-menu will let you unpin the tip which does not, as you might expect, cause the tip to disappear. Instead, the tip just drifts off to the right and now appears whenever you hit a breakpoint in any code window. This can be very helpful when you're trying to check one variable's value against another or want to change the value of the variable in the Data Tip. The bottom option in the mini-menu, which lets you leave a comment to yourself, can also be useful if your memory is as bad as mine.
The Debug menu also has some choices for managing Data Tips (including exporting and importing Data Tips if you want to keep some around after your debugging session ends). Data Tips are not an unalloyed blessing, if you have long variable names (names are usually displayed with their complete namespace): If the name disappears off the right side of your screen you won't get a scroll bar that will let you move to the right.
Posted by Peter Vogel on 07/23/2015