After double-clicking the script file in Unity and the system automatically opens VS, there is no "Solution Explorer" on the interface, and there is no prompt when writing part of the code. Then after bringing up the "Solution Explorer" in the view, the project will not be displayed.
Solution:
Check whether Unity and Visual Studio are related
1. Open the Unity project
2. Select Edit - Preferences... on the top menu bar and click to enter.
3. Select External Tools in the Preferences window
4. Set External Scripts Editor to the previously installed Visual Studio.