Async Try(blah) pattern [duplicate]

Maybe you could use Action<T> as the out param substitute

Example:

public async Task<bool> TryBlah(string key, Action<int> value)
{
    int something = await DoLongRunningIO();
    value(something)
    return true;         
}

Usage:

int myOutParam = 0;
if (await TryBlah("Something", value => myOutParam = value))
{
    // do somthing
}