Exposing Project Objects

Note

This article applies to Visual Studio 2015. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here

Custom project types can provide automation objects in order to allow access to the project using automation interfaces. Every project type is expected to provide the standard Project automation object that is accessed from Solution, which contains a collection of all projects that are open in the IDE. Each item in the project is expected to be exposed by a ProjectItem object accessed with ProjectItems. In addition to these standard automation objects, projects can choose to offer project-specific automation objects.

You can create custom root-level automation objects that you can access late-bound from the root DTE object using DTE.<customeObjectName> or DTE.GetObject(“<customObjectName>”). For example, Visual C++ creates C++ project-specific project collection called “VCProjects” that you can access using DTE.VCProjects or DTE.GetObject("VCProjects"). You can also create a Project.Object, which is unique for the project type, a Project.CodeModel, which can be queried for its most-derived object, a ProjectItem, which exposes ProjectItem.Object and a ProjectItem.FileCodeModel.

It is a common convention for projects to expose a custom, project-specific project collection. For example, Visual C++ creates a C++ specific project collection that you can then access using DTE.VCProjects or DTE.GetObject("VCProjects"). You can also create a Project.Object, which is unique for the project type, a Project.CodeModel, which can be queried for its most-derived object, a ProjectItem, which exposes ProjectItem.Object, and a ProjectItem.FileCodeModel.

To contribute a VSPackage-specific object for a project

1. Add the appropriate keys to the .pkgdef file of your VSPackage.

   For example, here are the .pkgdef settings for the C++ language project:

   [$RootKey$\Packages\{F1C25864-3097-11D2-A5C5-00C04F7968B4}\Automation]  
   "VCProjects"=""  
   [$RootKey$\Packages\{F1C25864-3097-11D2-A5C5-00C04F7968B4}\AutomationEvents]  
   "VCProjectEngineEventsObject"=""  
   

2. Implement the code in the GetAutomationObject method, as in the following example.

   STDMETHODIMP CVsPackage::GetAutomationObject(  
   /* [in]  */ LPCOLESTR       pszPropName,   
   /* [out] */ IDispatch **    ppIDispatch)  
   {  
   ExpectedPtrRet(pszPropName);  
   ExpectedPtrRet(ppIDispatch);  
   *ppIDispatch = NULL;  
   
       if (m_fZombie)  
           return E_UNEXPECTED;  
   
       if (_wcsicmp(pszPropName, g_wszAutomationProjects) == 0)  
       {  
           return GetAutomationProjects(ppIDispatch);  
       }  
       else if (_wcsicmp(pszPropName, g_wszAutomationProjectsEvents) == 0)  
       {  
           return CAutomationEvents::GetAutomationEvents(ppIDispatch);  
       }  
       else if (_wcsicmp(pszPropName, g_wszAutomationProjectItemsEvents) == 0)  
       {  
           return CAutomationEvents::GetAutomationEvents(ppIDispatch);  
       }  
       return E_INVALIDARG;  
   }   
   

   In the code, g_wszAutomationProjects is the name of your project collection. The GetAutomationProjects method creates an object that implements the Projects interface and returns an IDispatch pointer to the calling object, as shown in the following code example.

   HRESULT CVsPackage::GetAutomationProjects(/* [out] */ IDispatch ** ppIDispatch)  
   {  
       ExpectedPtrRet(ppIDispatch);  
       *ppIDispatch = NULL;  
   
       if (!m_srpAutomationProjects)  
       {  
           HRESULT hr = CACProjects::CreateInstance(&m_srpAutomationProjects);  
           IfFailRet(hr);  
           ExpectedExprRet(m_srpAutomationProjects != NULL);  
       }  
       return m_srpAutomationProjects.CopyTo(ppIDispatch);  
   }  
   

   You should choose a unique name for your automation object. Name conflicts are unpredictable, and collisions cause a conflicting object name to be arbitrarily thrown out if multiple project types use the same name. You should include your corporate name or some unique aspect of its product name in the name of the automation object.

   The custom Projects collection object is a convenience entry point for the remaining part of your project automation model. Your project object is also accessible from the Solution project collection. After you have created the appropriate code and registry entries that provide consumers with Projects collection objects, your implementation must provide remaining standard objects for the project model. For more information, see Project Modeling.

See Also

GetAutomationObject