Unable to build C# project

Question

I am having some weird problem.
When using this code I am unable to build, however it gives me no build errors.

the code

public void myMethod()
{              
    //This returns a string in JSON format.
    var jsonResponse = myApi.ReadMobileDevice("1");


    dynamic dynamicJson= JsonConvert.DeserializeObject(jsonResponse);

    //THIS LINE BREAKS MY BUILD. NO BUILD ERRORS SHOWN
    var jValue = dynamicJson["general.display_name"];
}

Can anyone tell me why my build braks, and also why no build errors are shown?

UPDATE - Output
*Also changed var to string

1>------ Build started: Project: Control, Configuration: Debug x86 ------
1>  Restoring NuGet packages...
1>  To prevent NuGet from downloading packages during build, open the Visual Studio Options dialog, click on the Package Manager node and uncheck 'Allow NuGet to download missing packages'.
1>  All packages listed in packages.config are already installed.
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(563,28,563,40): error CS0656: Missing compiler required member 'Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo.Create'
1>C:\ActacomProjects\DEV-Google\Control\Classes\DomainObjects\Schedules\HTTPSchedulesResponse.cs(41,34,41,36): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\Classes\DomainObjects\Schedules\HTTPSchedulesResponse.cs(87,30,87,32): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(1225,26,1225,45): warning CS0219: The variable 'recreateApplication' is assigned but its value is never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(1809,71,1809,74): warning CS0168: The variable 'dnf' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(1813,54,1813,56): warning CS0168: The variable 'ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(5017,34,5017,36): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(5087,42,5087,44): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(5154,42,5154,44): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(5192,42,5192,44): warning CS0168: The variable 'Ex' is declared but never used
1>C:\ActacomProjects\DEV-Google\Control\ModifyService.svc.cs(5267,42,5267,44): warning CS0168: The variable 'Ex' is declared but never used
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Solution 1

You have this error in your output:

Missing compiler required member 'Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo.Create'

You need to add a reference to the DLL Microsoft.CSharp.dll.

Solution 2

As similar to Saminathan S's comment in the accepted answer. If you are using .NETStandard projects (in my case NETStandard 2.0) you need to add Microsoft.CSharp from NuGet rather than as a reference in order to resolve this build error. I was using Visual Studio Community on a Mac.

Solution 3

Quick solution.

Right click on Packages > Add NuGet Packages... > Microsoft.CSharp

This worked for me. [Mac, Visual Studio 2017 Community]

Solution 4

You can also edit your .csproj file adding this, which has the same result as @the-senator said:

<PackageReference Include="Microsoft.CSharp" Version="4.5.0" />

View more solutions

Comments

[Saminathan S]

Problem solved for me when I added System.Core in-addition to Microsoft.CSharp

[Sakthivel]

I have to add Nuget.CSharp in xamarin.Forms project as projects target .Net core 2.x and CSharp assembly cannot be explicitly added to portable project. worked.

[frank]

I use the same why from Sakthivel by adding Microsoft.CSharp from nuget to the .net standard project to fix this issue

[jmdon]

Same for me in VS2017 Professional on Windows. Why this wasn't included in the project template remains a mystery.

[Renzo Ciot]

I added the Nuget Package Microsoft.CSharp, but I have the same error.

[GaidinD]

Same for me using VS2019 Community on Windows x64 with NETStandard2.0.