This should hopefully be a simple one.
I would like to add an extension method to the System.Web.Mvc.ViewPage< T > class.
How should this extension method look?
My first intuitive thought is something like this:
namespace System.Web.Mvc
{
public static class ViewPageExtensions
{
public static string GetDefaultPageTitle(this ViewPage<Type> v)
{
return "";
}
}
}
Solution
The general solution is this answer.
The specific solution to extending the System.Web.Mvc.ViewPage class is my answer below, which started from the general solution.
The difference is in the specific case you need both a generically typed method declaration AND a statement to enforce the generic type as a reference type.
Glenn Block has a good example of implementing a
ForEach
extension method toIEnumerable<T>
.From his blog post:
Thanks leddt. Doing that yielded the error:
which pointed me to this page, which yielded this solution:
I don't have VS installed on my current machine, but I think the syntax would be:
It just needs the generic type specifier on the function:
Edit: Just missed it by seconds!
You may also need/wish to add the "new()" qualifier to the generic type (i.e. "where T : class, new()" to enforce that T is both a reference type (class) and has a parameterless constructor.
If you want the extension to only be available for the specified type you simply just need to specify the actual type you will be handling
something like...
Note intellisense will then only display the extension method when you declare your (in this case) ViewPage with the matching type.
Also, best not to use the System.Web.Mvc namespace, I know its convenient to not have to include your namespace in the usings section, but its far more maintainable if you create your own extensions namespace for your extension functions.