Microsoft.VisualStudio.Project.SingleFileGeneratorFactory.CreateGeneratorInstance C# (CSharp) Method

        public virtual int CreateGeneratorInstance(string progId, out int generatesDesignTimeSource, out int generatesSharedDesignTimeSource, out int useTempPEFlag, out IVsSingleFileGenerator generate)
        {
            Guid genGuid;
            ErrorHandler.ThrowOnFailure(this.GetGeneratorInformation(progId, out generatesDesignTimeSource, out generatesSharedDesignTimeSource, out useTempPEFlag, out genGuid));

            //Create the single file generator and pass it out. Check to see if it is in the cache
            if(!this.generatorsMap.ContainsKey(progId) || ((this.generatorsMap[progId]).Generator == null))
            {
                Guid riid = VSConstants.IID_IUnknown;
                uint dwClsCtx = (uint)CLSCTX.CLSCTX_INPROC_SERVER;
                IntPtr genIUnknown = IntPtr.Zero;
                //create a new one.
                ErrorHandler.ThrowOnFailure(this.LocalRegistry.CreateInstance(genGuid, null, ref riid, dwClsCtx, out genIUnknown));
                if(genIUnknown != IntPtr.Zero)
                {
                    try
                    {
                        object generator = Marshal.GetObjectForIUnknown(genIUnknown);
                        //Build the generator meta data object and cache it.
                        GeneratorMetaData genData = new GeneratorMetaData();
                        genData.GeneratesDesignTimeSource = generatesDesignTimeSource;
                        genData.GeneratesSharedDesignTimeSource = generatesSharedDesignTimeSource;
                        genData.UseDesignTimeCompilationFlag = useTempPEFlag;
                        genData.GeneratorClsid = genGuid;
                        genData.Generator = generator;
                        this.generatorsMap[progId] = genData;
                    }
                    finally
                    {
                        Marshal.Release(genIUnknown);
                    }
                }
            }

            generate = (this.generatorsMap[progId]).Generator as IVsSingleFileGenerator;

            return VSConstants.S_OK;
        }

        /// <summary>
        /// Invokes the specified generator
        /// </summary>
        /// <param name="fileNode">The node on which to invoke the generator.</param>
        protected internal virtual void InvokeGenerator(FileNode fileNode)
        {
            if(fileNode == null)
            {
                throw new ArgumentNullException("fileNode");
            }

            SingleFileGeneratorNodeProperties nodeproperties = fileNode.NodeProperties as SingleFileGeneratorNodeProperties;
            if(nodeproperties == null)
            {
                throw new InvalidOperationException();
            }

            string customToolProgID = nodeproperties.CustomTool;
            if(string.IsNullOrEmpty(customToolProgID))
            {
                return;
            }

            string customToolNamespace = nodeproperties.CustomToolNamespace;

            try
            {
                if(!this.runningGenerator)
                {
                    //Get the buffer contents for the current node
                    string moniker = fileNode.GetMkDocument();

                    this.runningGenerator = true;

                    //Get the generator
                    IVsSingleFileGenerator generator;
                    int generateDesignTimeSource;
                    int generateSharedDesignTimeSource;
                    int generateTempPE;
                    SingleFileGeneratorFactory factory = new SingleFileGeneratorFactory(this.projectMgr.ProjectGuid, this.projectMgr.Site);
                    ErrorHandler.ThrowOnFailure(factory.CreateGeneratorInstance(customToolProgID, out generateDesignTimeSource, out generateSharedDesignTimeSource, out generateTempPE, out generator));

                    //Check to see if the generator supports siting
                    IObjectWithSite objWithSite = generator as IObjectWithSite;
                    if(objWithSite != null)
                    {
                        objWithSite.SetSite(fileNode.OleServiceProvider);
                    }

                    //Determine the namespace
                    if(string.IsNullOrEmpty(customToolNamespace))
                    {
                        customToolNamespace = this.ComputeNamespace(moniker);
                    }

                    //Run the generator
                    IntPtr[] output = new IntPtr[1];
                    output[0] = IntPtr.Zero;
                    uint outPutSize;
                    string extension;
                    ErrorHandler.ThrowOnFailure(generator.DefaultExtension(out extension));

                    //Find if any dependent node exists
                    string dependentNodeName = Path.GetFileNameWithoutExtension(fileNode.FileName) + extension;
                    HierarchyNode dependentNode = fileNode.FirstChild;
                    while(dependentNode != null)
                    {
                        if(string.Compare(dependentNode.ItemNode.GetMetadata(ProjectFileConstants.DependentUpon), fileNode.FileName, StringComparison.OrdinalIgnoreCase) == 0)
                        {
                            dependentNodeName = ((FileNode)dependentNode).FileName;
                            break;
                        }

                        dependentNode = dependentNode.NextSibling;
                    }

                    //If you found a dependent node.
                    if(dependentNode != null)
                    {
                        //Then check out the node and dependent node from SCC
                        if(!this.CanEditFile(dependentNode.GetMkDocument()))
                        {
                            throw Marshal.GetExceptionForHR(VSConstants.OLE_E_PROMPTSAVECANCELLED);
                        }
                    }
                    else //It is a new node to be added to the project
                    {
                        // Check out the project file if necessary.
                        if(!this.projectMgr.QueryEditProjectFile(false))
                        {
                            throw Marshal.GetExceptionForHR(VSConstants.OLE_E_PROMPTSAVECANCELLED);
                        }
                    }
                    IVsTextStream stream;
                    string inputFileContents = this.GetBufferContents(moniker, out stream);

                    ErrorHandler.ThrowOnFailure(generator.Generate(moniker, inputFileContents, customToolNamespace, output, out outPutSize, this));
                    byte[] data = new byte[outPutSize];

                    if(output[0] != IntPtr.Zero)
                    {
                        Marshal.Copy(output[0], data, 0, (int)outPutSize);
                        Marshal.FreeCoTaskMem(output[0]);
                    }

                    //Todo - Create a file and add it to the Project
                    this.UpdateGeneratedCodeFile(fileNode, data, (int)outPutSize, dependentNodeName);
                }
            }
            finally
            {
                this.runningGenerator = false;
            }
        }