无法在VSLangProj中找到VSProject接口

Question

编辑：注意：我正在使用Visual Studio 2015

我正在尝试使用VSIX项目编写VisualStudio扩展，它显示当前加载的解决方案的所有引用。

我能够使用下面的代码获取当前的解决方案和项目（事实上所有项目）。

我将问题代码分离为GetProjectReferences方法 我无法参考VSLangProj.VSProject。

 DTE2 dte2 = Package.GetGlobalService(typeof(DTE)) as     
 var sol = dte2.Solution;
 var projs = sol.Projects;

 foreach (Project project in projs)
 {
     if (project.Kind == ProjectKinds.vsProjectKindSolutionFolder)
     {   
         //Ignoring Solution Folders for now
     }
     else
     {
         //This method tries to get the refernces
         AppendProject(sb,project);
     }               
 }

 private void GetProjectReferences(StringBuilder sb, Project project)
    {            
        var vsProject = project.Object as VSLangProj.VSProject;
        var references = vsProject.References as VSLangProj.References;
        sb.AppendLine(project.Name + ": " + references.Count);
        int counter = 1;
        foreach (var reference in references)
        {
            sb.AppendLine((counter++)+": " + reference.Name + " (" + reference.Path +")");
        }
    }

它与microsoft的文档不匹配，我无法在任何其他Microsoft的库（VSLangProj2和VSLangProj80）中找到此接口，如下所述： https://msdn.microsoft.com/en-us/library/vslangproj.aspx

我也试过用VB来测试代码，但无济于事： https://msdn.microsoft.com/en-us/library/vslangproj.vsproject.aspx

' Macro Editor
' This example retrieves the VSProject object if the first project
' the solution is a Visual Basic or C# project. This routine assumes
' that the solution contains at least one project.
Imports VSLangProj
Sub VSProjectExample()
   Dim aProject As Project
   Dim aVSProject As VSProject

   aProject = DTE.Solution.Projects.Item(1)
   If (aProject.Kind = PrjKind.prjKindVBProject) _
   Or (aProject.Kind = PrjKind.prjKindCSharpProject) Then
      aVSProject = CType(DTE.Solution.Projects.Item(1).Object, VSProject)
      MsgBox(aVSProject.Project.FullName)
   Else
      MsgBox("The first project is not a Visual Basic or C# project.")
   End If
End Sub

Answer 1

感谢@ErikEJ，我能够找到遗漏的东西：我没有VSLangProj参考。 它位于参考管理器

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