Visual Studio Architecture Code Generation - Create List<type> rather than IEnumerable<type>

Question

Is it possible to configure an Association in a Visual Studio (2013) class diagram so that when the code is generated from it that it creates a property with type List<MyClass> or even ICollection<MyClass> rather than it's default of IEnumerable<MyClass>?

Answer 1

Yes, it is possible to change the output. Visual Studio uses T4 templates to generate code from the Architecture tools.

You can find the templates at C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\IDE\Extensions\Microsoft\Architecture Tools\Extensibility\Templates\Text (remove (x86) if you have a 32-bit machine).

Use the following steps to change the generated code to IList<T> instead of the default IEnumerable<T>:

1. Back up all templates to a different directory on your machine (better be safe than sorry)
2. Open CSharpHelper.t4 from the above directory

3. Locate the method named ElementType(IType type, bool isEnumerable = false)

    private static string ElementType(IType type, bool isEnumerable = false)
   {
       string text = string.Empty;
       if (type == null)
       {
           text = "object";
       }
       else 
       {
           text = TypeName(type);
       }
   
       if(!string.IsNullOrWhiteSpace(text) && isEnumerable)
       {
          //SO Change IEnumerable to IList here
           text = "IEnumerable<" + text + ">";
       }
   
       return text;
   }
   

4. Change the string IEnumerable to whatever you want (see my comment starting with SO)

5. Save the T4 file and generate your code from visual studio

You can even write your own T4 Templates and instruct visual studio to use them when generating code, more details on MSDN.