Can't use DBNull in .NET Standard 1.4?

Question

I am creating a class library that will be used in a WPF project and a .NET Core project.

For the following code:

    public class MyClass
    {
        private void MyFunction(object o)
        {
            if (o == DBNull)
            {
                //ommitted
            }
        }
    }

I am getting the following error:

The name 'DBNull' does not exist in the current context

This is a .NET Standard Class Library Project created in Visual Studio 2017.

Both my .NET Core project and WPF Project allow the use of DBNull.

Answer 1

You need to add the NuGet package System.Data.Common to your project to be able to use DBNull in netstandard1.4 via the NuGet package manager or via console:

dotnet add package System.Data.Common

In .NET Standard 2.0, it will be available automatically.