Easily Adding SafeControls in SharePoint 2010 with Visual Studio 2010

Many SharePoint developers know that deploying your SharePoint customization to a SharePoint server often requires you to tinker the web.config of the sites where you’d like to see the customization in action. You can do these web.config modifications manually (not advisable), or automate them with the help of the SPWebConfigModification class from the Object Model. But quite often it’s not even necessary to use that class; when you deploy your customizations with the help of a Solution (.WSP file), like you should, the Solution deployment mechanism can modify the Web.Config to apply the most commonly used changes

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Easily Adding SafeControls in SharePoint 2010 with Visual Studio 2010