How to add ResourceDictionary.xaml to your existing c# WPF Application

//How to add ResourceDictionary.xaml to your existing c# WPF Application
 //Goto ->Project, Add New Existing Project, then browse your ResourceDictionary
//-> copy the highlighted text inside app.xaml between Application.Resources
//please note that my ResourceDictionary1.xaml is inside a folder name Resources
//remove ResourceDictionary2.xaml if it is not available and rename ResourceDictionary1.xaml according
//to your Resource Dictionary file.