xamarinmac 
namespace Microsoft.Build.Framework
{
    public class TaskStartedEventArgs : BuildStatusEventArgs
    {
        public override string Message { get; }
    }
}
.NET
5.06.07.08.09.010.0
.NET Core
2.02.12.23.03.1
.NET Framework
4.6.14.6.24.74.7.14.7.24.84.8.1
.NET Standard
2.02.1
Information specific to xamarinmac
Assembly

Microsoft.Build.Framework , Version=15.1.0.0, PublicKeyToken=b03f5f7f11d50a3a

Referencing

Your project needs a package reference to Microsoft.Build.Framework.

Package Microsoft.Build.Framework (17.13.9) netstandard2.0
Platform Restrictions

This framework does not have platform annotations.

  • Built-in API
  • Package-provided API