A simple project demonstrating converting uploaded file to Base64 in Index.razor page. Just a slight alteration of the code found in https://docs.microsoft.com/en-us/aspnet/core/blazor/file-uploads?view=aspnetcore-6.0&pivots=webassembly applied to a project created with dotnet new blazorwasm.

Try it on: https://esteinmann.github.io/blazor-file-upload

Note that files are not uploaded to any remote server in this demonstration, the conversion to Base64 happens client side.