I have a WebUploadedFile (text) in memory.
Is it possible to get it directly into a Textinputstream w/o saving it to disk first?
You don’t need too - you have it in memory.
TextInputStream is for streaming data from storage instead of loading the entire file at once and reading it. Of course we often do that with small files anyway but not the point.
Use the WebUploadedFile.Data property to traverse the memory.