async/await exception handling pattern

Question

I have the following reoccurring try/catch pattern in my code. Using a try/catch block to handle any exceptions thrown when calling a method in orionProxy.

async private void doGetContacts() {     try {         currentContacts = await orionProxy.GetContacts (); // call method in orionProxy         ShowContacts (); // do something after task is complete     }     catch (Exception e) {         orionProxy.HandleException (e); // handle thrown exception     } } 

What I would like to write is something like the following.

async private void doGetContacts() {     currentContacts = await orionProxy.CheckForException(orionProxy.GetContacts ());     ShowContacts (); // do something after task is complete but shouldn't run on exception } 

Any pointers/suggestions? I've tried various forms of Actions/Tasks/Lambdas but nothing will properly trap the exception in orionProxy.CheckForException(?) so ShowContacts doesn't run.

Answer 1

I don't see why it wouldn't work, assuming GetContacts is an async method:

public async Task<T> CheckForExceptionAsync<T>(Task<T> source) {   try   {     return await source;   }   catch (Exception ex)   {     HandleException(ex);     return default(T);   } } 

On a side note, you should avoid async void (as I describe in my MSDN article) and end your async method names with the Async suffix.