This code is obsoleted. Please download or clone our most updated open-source GroupDocs.Annotation for .NET MVC sample application here. Furthermore, have a look at this demo video. Steps to run this application are easy and clearly mentioned in GitHub repository readme file.
So to resolve this error, I followed one link but it did not worked.
Also I did not understand how to implement this code in MVC application. I have to show viewer/annotation in my MVC page but I did not understand how to implement this.
Please have a look at this related GitHub issue. Following steps must fix your issue:
Reinstall Node
Delete node_modules folder
Run npm cache clean --force
Remove npm and npm-cache folders from C:\Users\{username}\AppData\Roaming
Run npm install -g @angular/cli@latest and npm i
Build the solution in Visual Studio
Please note that GroupDocs.Annotation for .NET is a UI independent API that could be integrated in any .NET application without any third party tool or software dependency.
The demo project we shared with you is just a demonstration of some of the API features. Please go through this developer guide and this open-source console example project to get an idea about the API features. Later, you can implement those features in your MVC application.
Can you please provide me any code that has integration with MVC UI. I tried this a lot but not sure how to integrate with MVC UI. I have to edit my document and save it in local disk.
I have just requirement of adding annotate/viewer in UI and edit documents and save again on the same document location.
Do I need to make custom viewer or it will automatically render viewer in UI?
You have to make a custom viewer. Like we elaborated earlier that API is UI-Independent. You can implement it in any of your web/Windows form or console applications.