RSS Feed Aggregator and Blogging Smart Client

// Copyright � 2005 by Omar Al Zabir. All rights are reserved.
// 
// If you like this code then feel free to go ahead and use it.
// The only thing I ask is that you don't remove or alter my copyright notice.
//
// Your use of this software is entirely at your own risk. I make no claims or
// warrantees about the reliability or fitness of this code for any particular purpose.
// If you make changes or additions to this code please mark your code as being yours.
// 
// website http://www.oazabir.com, email OmarAlZabir@gmail.com, msn oazabir@hotmail.com

using System;
using System.Reflection;
using System.Runtime.InteropServices;

using System.Xml;

namespace RSSCommon.Helper
{
	/// <summary>
	/// Summary description for OutlookHelper.
	/// </summary>
	public class OutlookHelper
	{
		public static object GetObject( string typeName )
		{
			Type objectType = Type.GetTypeFromProgID(typeName);
			return Activator.CreateInstance( objectType );			
		}

		public static object GetProperty( object obj, string propertyName )
		{
			return obj.GetType().InvokeMember( propertyName,
				BindingFlags.GetProperty, null, obj, null );
		}

		public static object GetProperty( object obj, string propertyName, object defaultValue )
		{
			try
			{
				return obj.GetType().InvokeMember( propertyName,
					BindingFlags.GetProperty, null, obj, null );
			}
			catch
			{
				return defaultValue;
			}
		}

		public static object GetItem( object obj, int index )
		{
			object [] parameters = new Object[1];
			parameters[0] = index;
			return obj.GetType().InvokeMember( "Item",
				BindingFlags.GetProperty, null, obj, parameters );
		}
		public static object GetItem( object obj, string name )
		{
			object [] parameters = new Object[1];
			parameters[0] = name;
			return obj.GetType().InvokeMember( "Item",
				BindingFlags.GetProperty, null, obj, parameters );
		}
		public static object SetProperty( object obj, string propertyName, object value )
		{
			object [] parameters = new Object[1];
			parameters[0] = value;
			return obj.GetType().InvokeMember( propertyName, BindingFlags.SetProperty,
				null, obj, parameters );
		}

		public static object CallMethod( object obj, string methodName, params object [] parameters )
		{
			return obj.GetType().InvokeMember( methodName, BindingFlags.InvokeMethod, null, obj,
				parameters );
		}

		public static void StartOutlook( ref object app, ref object name )
		{
			try
			{
				// Try to get existing outlook instance
				app = Marshal.GetActiveObject("Outlook.Application");
				name = GetProperty( app, "Session" );
			}
			catch
			{
				// Create new instance of outlook
				app = GetObject("Outlook.Application");
				name = GetProperty( app, "Session" );
			}
		}

		public static bool EnsureExplorer( object app, object name )
		{
			// Outlook normally remains invisible when new instance created, let's show it minimized
			bool isOutlookInvisible = false;

			object explorer = CallMethod( app, "ActiveExplorer" );
			object explorers = GetProperty( app, "Explorers" );
				
			if( null == explorer )
			{
				isOutlookInvisible = true;

				// Outlook was not open, we are not loading the first outlook. So,
				// let's take some precaution

				object inbox = CallMethod( name, "GetDefaultFolder", 6 ); //OlDefaultFolders.olFolderInbox = 6

				explorer = CallMethod( explorers, "Add", inbox, 1 ); //Outlook.OlWindowState.olMinimized = 1

				Marshal.ReleaseComObject( inbox );
				inbox = null;
			}

			// Force outlook to show its face
			CallMethod( explorer, "Display" );
			SetProperty( explorer, "WindowState", 1 );
			//CallMethod( explorer, "Activate" );
			
			Marshal.ReleaseComObject( explorer );
			explorer = null;

			Marshal.ReleaseComObject( explorers );
			explorers = null;

			return isOutlookInvisible;
		}

		public static void CloseOutlook( object app )
		{
			// Get explorers and close each of them
			object explorer = null;
				
			while( (explorer = CallMethod( app, "ActiveExplorer" )) != null )
			{
				CallMethod( explorer, "Close" );

				Marshal.ReleaseComObject( explorer );
			}			
			
			// shut down outlook
			CallMethod( app, "Quit" );
		}

		public static string SelectFolderPath()
		{
			// Show outlook folder picker
			object app = null, name = null;

			StartOutlook( ref app, ref name );

			// Ensure at least one explorer is visible otherwise we cannot show the folder
			// picker
			bool isOutlookInvisible = EnsureExplorer( app, name );
			
			object folder = CallMethod( name, "PickFolder" );

			string path = null;
			// Get the selected folder name
			if( null != folder )
				path = GetProperty( folder, "FolderPath" ) as string;
			
			if( null != folder )
				Marshal.ReleaseComObject( folder );
			folder = null;

			Marshal.ReleaseComObject( name );
			name = null;

			if( isOutlookInvisible )
				CloseOutlook(app);

			Marshal.ReleaseComObject( app );			
			app = null;			

			// Outlook still hangs around in the task manager until we call this
			GC.Collect();

			return path;
		}

		/*
		public static MAPIFolder GetFolderFromPath( string path )
		{
			Outlook.Application app = new Outlook.ApplicationClass();
			Outlook.NameSpace name = app.Session;

			path = path.TrimStart('\\');
			string [] folders = path.Split('\\');

			Outlook.MAPIFolder mapiFolder = name.Folders[ folders[0] ];
			
			// See if the folder has been renamed
			if( null == mapiFolder )
				return null;
			for( int i = 1; i < folders.Length; i ++ )
			{
				string folderName = folders[i];

				try
				{
					mapiFolder = mapiFolder.Folders[ folderName ];
				}
				catch( System.Exception x )
				{
					mapiFolder = null;
				}

				// The folder may have been renamed
				if( null == mapiFolder )
					return null;
			}

			return mapiFolder;
		}
		*/

		public static object EnsureFolderPath( object name, string path )
		{
			path = path.TrimStart('\\');
			string [] folders = path.Split('\\');

			// See if the first folder in the path exists
			object rootFolders = GetProperty( name, "Folders" );
			object mapiFolder = null;
			try
			{
				 mapiFolder = GetItem( rootFolders, folders[0] );
			}
			catch( Exception x )
			{
				throw new ApplicationException("Base folder not defined properly. Go to 'Options' and select Outlook Base Folder", x );
			}
			
			Marshal.ReleaseComObject( rootFolders );

			// The first folder does not exist, may be the personal folder was closed or deleted,
			// We can abort safely.
			if( null == mapiFolder )
				return null;

			for( int i = 1; i < folders.Length; i ++ )
			{
				string folderName = folders[i];

				object mapiFolders = GetProperty( mapiFolder, "Folders" );

				// See if the child folder exists
				object childFolder = null;
				try
				{
					childFolder = GetItem( mapiFolders, folderName );
				}
				catch {}

				// The folder may have been renamed or deleted
				if( null == childFolder )
				{
					// Create a new folder using the name
					childFolder = CallMethod( mapiFolders, "Add", folderName, Missing.Value );									
				}

				mapiFolder = childFolder;

				// Release the child folders collection
				Marshal.ReleaseComObject( mapiFolders );
				mapiFolders = null;
			}

			// Return the last created folder
			return mapiFolder;
		}

		/// <summary>
		/// Ensures whether we have the proper view for the specified folder
		/// </summary>
		/// <param name="folder"></param>
		public static void EnsureView( object folder, string viewXmlPath )
		{
			if( !System.IO.File.Exists( viewXmlPath ) ) return;
			// 1. Load the view xml file to find out the view name. We must not create duplicate view with 
			// same name
			XmlDocument doc = new XmlDocument();
			doc.Load( viewXmlPath );

			XmlElement viewNameElement = (XmlElement)doc.DocumentElement.SelectSingleNode("viewname");
			string viewName = viewNameElement.InnerText.Trim();

			// 2. Check if this view has already been created
			object views = GetProperty( folder, "Views" );

			object existingView = GetItem( views, viewName );

			// 3. If the view already exist, apply it, otherwise create it
			if( null != existingView )
			{
				// Apply the existing view
				CallMethod( existingView, "Apply" );

				// It has already been created, so let's skip
				Marshal.ReleaseComObject( existingView );
			}
			else
			{
				// Create the new view
				object newView = CallMethod( views, "Add", viewName, 0, 2 );						
				// Outlook.OlViewType.olTableView = 0
				// Outlook.OlViewSaveOption.olViewSaveOptionAllFoldersOfType = 2

				SetProperty( newView, "XML", doc.OuterXml );
				
				CallMethod( newView, "Save" );
				CallMethod( newView, "Apply" );
			}
			
		}

	}
}