9
votes

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'.'

Please See the image

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??

2
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 CoreNirman
Thanks for the reply.. Can you please tell me which library do I need to add so as to get this work.Karthik Saxena

2 Answers

6
votes

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

0
votes

I believe you have installed packages that are targeting only for Net MVC and therefore has a dependencies on System.Web.HttpContextBase which don't exist in Net Core. To fix this issue you need to find which package you installed don't have support for your Net core and install an alternative