A long running problem in ASP.NET has been the inability to handle returning large JSON files without consuming a lot of memory. The default behavior for the framework is to buffer the entire output at once, convert it en masse to JSON, and then start feeding the results to the client. This can lead to out-of-memory situations if the amount of data is large enough.

The inability to stream results was never a fundamental problem for ASP.NET. When working with simpler formats such as CSV, the developer has always had the ability write directly to the result stream.

Starting with ASP.NET Core 5, the Utf8JsonWriter class can be used for the same effect. The code has a few complexities to it, such as the need to explicitly disable buffering, but can work if you follow the instructions provided by Alexander Vasilyev.

#dotnet #aspdotnet core #dotnet 6 #ef core