 <p>I am not completely sure what you want to achieve, exactly. But you <em>can</em> do something like:</p> <pre><code>IsHandled = ev =&gt; { ev(this, args); return args.Handled; }; </code></pre> <p>Even though I am not sure this is more readable, faster, cleaner, or anything like that. I would just go with something like</p> <pre><code>if (ErrorConfiguration != null) ErrorConfiguration(this, args); if (!args.Handled) error(this, args); </code></pre>