How do I fix a "System.Net.Http.HttpRequestException: TypeError: Failed to fetch" in Blazor WebAssembly?

Question

The code below, runs for about fifteen seconds on the "dataFs = await _Http.GetStreamAsync(BODIST_DATA_HTTPNAME)" line before failing with a "System.Net.Http.HttpRequestException: TypeError: Failed to fetch".

        public async Task<Double> EffectivePipCount(HttpClient _Http, Int64 _PositionId)
        {
            Double retVal = Double.NaN;
            using (Stream locnFs = await _Http.GetStreamAsync(BODIST_LOCATION_FILENAME)
                            , dataFs = await _Http.GetStreamAsync(BODIST_DATA_FILENAME))
            {
                retVal = EffectivePipCount(_PositionId, locnFs, dataFs);
            }
            return retVal;
        }

The file in question is about four gigabytes in size.

This is in Blazor WebAssembly app, so I want an Http equivalent to a FileStream, where I can seek and then read the hundreds of bytes I want. Small files in the same directory work fine.

If the problem is a timeout because of the file size, what should I be using instead of HttpClient.GetStreamAsync()?

Answer 1

My best guess is that GetStreamAsync() pulls down the whole file. Using http.GetFromJsonAsync solves the problem.