This was tip #19 in my TechEd VS 2008 IDE Tips and Tricks talk.

Whenever you are debugging and want to change the contents of a variable, you can drag and drop the variable into the Watch Window.  But, you can also use data tips to change the variable without leaving the editor.

Hover over a variable when you have hit a breakpoint.  You’ll notice a glorified tool tip appear.  This is actually a “data tip”.  You can click on the value of the variable to go into an edit mode.  Change the contents of the variable and press Enter to commit. 

If you have the Autos window open, you’ll notice the color change, implying the commit was successful.

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