Azure WebJobs, catch error to prevent host failure

问题

Assume a simple HostBuilder configuration as described here.

Just like that:

static async Task Main()
{
    var builder = new HostBuilder();
    builder.ConfigureWebJobs(b => b
           .AddAzureStorageCoreServices()
           .AddAzureStorage()
           .AddTimers())
    var host = builder.Build();
    using (host)
    {
        await host.RunAsync();
    }
}

There seem to be some situations where Exceptions can happen, not inside the QueueTrigger or TimerTrigger functions directly (these are catched gracefully), but on a global scope. Some of them I already noticed were HTTP 409 Conflict responses, TimeoutException raised, etc (they seem to happen right before entering the actual Function, e.g. when accessing the Queue for Messages read). And the whole host app is shut down. The Webjob needs to restart and I don't want that. The point is, I don't want to tackle these specific issues here.

How can I catch the exception and prevent the host from being destroyed? It seems that I can't even put a try/catch around await host.RunAsync(), the catch was not triggered. I added Logging just before the host run and inside the catch; After some time I had multiple "Starting..." logs but no "Error occured" log.

来源：https://stackoverflow.com/questions/60304305/azure-webjobs-catch-error-to-prevent-host-failure