System.TypeLoadException: 'Could not load type 'System.Web.HttpContextBase' from assembly 'System.Web,

Question

Whenever I try to load the Chart using System.Web.Helpers namespace in Asp.net Core I get this Exception.

System.TypeLoadException: 'Could not load type 'System.Web.HttpContextBase' from assembly 'System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.'

new System.Web.Helpers.Chart(width: 800, height: 200).AddTitle("My Chart").AddSeries(chartType: "column", 
           xValue: new[] { _context.DemoTable.Select(o => o.Month) },
           yValues: new[] { _context.DemoTable.Select(o => o.AutomationPercentage) }
          ).Write("png");

What am I doing wrong here??

Solution

the class exists in other namespace so make sure you're using Microsoft.AspNetCore.Mvc and not the .NET framework version.

Comments

[Nirman]

System.Web.HttpContextBase is part of System.Web assembly. .NET core by default does not add reference of this DLL, and it is also not preferred to do so. I think System.Web.Helpers is .NET Framework library and not .NET Core

[Karthik Saxena]

Thanks for the reply.. Can you please tell me which library do I need to add so as to get this work.

[Ross Gustafson]

I get this error while trying to test .NET Framework code from a xUnit .NET Core unit test. What do I need to add to my .NET core project to make this work?