Options, Text Editor, File Extension
This Options dialog allows you to specify how all files with certain file extensions will be handled by the Visual Studio integrated development environment (IDE). For each Extension that you enter, you can select an Editing Experience. This allows you to choose the IDE editor or designer in which documents of a certain type will open. To display these options, choose Options from the Tools menu, expand the Text Editor node, and select File Extension.
When you select an option "with Encoding," a dialog will be displayed whenever you open a document of that type that allows you to select an encoding scheme for that document. This can be helpful if you are preparing versions of your project documents for use on different platforms or in different target languages.
The dialog boxes and menu commands you see might differ from those described in Help depending on your active settings or edition. To change your settings, choose Import and Export Settings on the Tools menu. For more information, see Customizing Development Settings in Visual Studio.