C#中的尖括号语法是什么意思

Question

I am reading this book, and it tries to use initializer to Create the DB each time the application runs, so the code snippet is like this:

protected void Application_Start() {
    Database.SetInitializer(new DropCreateDatabaseAlways<MusicStoreDB>());

    AreaRegistration.RegisterAllAreas();
    FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
    RouteConfig.RegisterRoutes(RouteTable.Routes);
    BundleConfig.RegisterBundles(BundleTable.Bundles);
}

I can't understand this part:

 new DropCreateDatabaseAlways<MusicStoreDB>()

What is this syntax? what does <MusicStoreDB>() mean?

I know it's not a fancy question, but I need help here.

Thanks.

Answer 1

That syntax is called generics . In a nutshell (a very tiny nutshell), imagine that your app had more than 1 database (eg MusicStoreDB, MovieStoreDB, etc), you could use the same DropCreateDatabaseAlways class with the different db types. In other words, generics let you define classes and functions that can act on many different types, for example

List<int>, List<string>, List<MyAwesomeClass>

Answer 2

DropCreateDatabaseAlways is the database intializer base class. MusicStoreDB is the database which will be dropped and re-created everytime the application starts. DropCreateDatabaseAlways<MusicStoreDB>() is the code that does that