How can i see unity code?

hi!
I want to see like this

https://github.com/liuqiaosz/Unity/blob/master/UGUI源代码/UnityEngine.UI/UI/Core/Button.cs

However, if you move from my project to definition, it comes out like this.

 

Code is included in the project through dll's, so the source isn't available. There's two options:

- Use Rider to edit code, or get Resharper for Visual Studio. Both decompile into source on the fly, and give you a pretty good representation of what the source is like

- Check the publicly available source on Github. That requires manually searching, though, which is a bit of a pain.

Ideally you'd have a button in your editor that jump straight to the source on GitHub, but I'm not aware of any such plugin for any editors.