VS Code snippets for files with specific extension

Question

Visual Studio Code allows creating snippets, separated for various language syntaxes. But is it possible to specify not only language, but also extension of a particular file for created snippet?

For example: I want to create snippet specifically for c# .csproj file. This file has xml syntax, and I could create snippet as an xml snippet, but I don't want to see this snippet in other xml files except .csproj.