Question

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 the attribute.

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

Answer 1

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>