Workflow 4.0 and System.Attribute

workflows seem to be created straight from Xaml. How then is would it be possible to include a System.Attribute on my workflow classes?

The only ways i can think of are a bit crap:

Have a corresponding code file for each Activity.xaml:

[MyCustomAttribute("hello")]
public abstract class MyPointlessWorkflowBase : System.Activity
{

}

And then having my .xaml inherit from the base (i don't even know if this is possible)? But this sucks as i have to an extra class for each Workflow that requires th开发者_运维技巧e attribute.

is there anyway to code activities like they were normal classes before you slap the .xaml over it?

A XAML file generates a class with a partial keyword before it gets compiled so you can create a partial class with the same name and add the attribute there.

[MyCustomAttribute("hello")]
public partial class MyWorkflow : Activity
{
}

Alternatively you can add an attribute in XAML using the x:ClassAttributes element and add them that way.

<p:Activity x:Class="WorkflowConsoleApplication1.MyWorkflow"
            xmlns:s="clr-namespace:System;assembly=mscorlib"
            xmlns:my="......"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <x:ClassAttributes>
      <my:MyCustomAttribute>
        <x:Arguments>
          <s:String>hello</s:String>
        </x:Arguments>
      </my:MyCustomAttribute>
    </x:ClassAttributes>
</p:Activity>