My name
is
Jon Skeet

Is it necessary to await a single asynchronous call

If I'm returning the result of a single asynchronous function e.g. in a service between application layers, is there any difference between:

    public Task<byte[]> GetInsurancePolicyDocument(string itineraryReference)
    {
        return this.coreItineraryDocumentService.GetInsurancePolicyDocument(itineraryReference);
    }

And:

    public async Task<byte[]> GetInsurancePolicyDocument(string itineraryReference)
    {
        return await this.coreItineraryDocumentService.GetInsurancePolicyDocument(itineraryReference);
    }

There are a few very subtle differences in some cases - for example, if the original Task returns with a status of Faulted but with an OperationCanceledException then the async version would return a task with a status of Canceled... but unless you really need any of that subtlety, it would generally be better to go with your first code and avoid the (very slight) overhead of wrapping it.

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