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Column Guides in Visual Studio
A lot of coding guidelines specify the maximum length for a line of code. For instance in the CLR, Microsoft like to keep lines of code under 110 characters long. Visual Studio has a feature which lets you display a vertical line at the column of your choosing to help visually see when a line is getting too long. This does involve mucking in the registry so the usual disclaimers apply.
To enable this feature, set:
[HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\8.0\Text Editor]
"Guides"="RGB(192,192,192) 110"
The values passed to the RGB function let you specify the color of the line, and the number following tells Visual Studio at what column to display it. The