问题
Am creating a outlook add-in to track mail processing from mailbox. Am wrapping the folders and the items(adding some events into it ) and storing them in a local list to avoid GC clearing all the events after first execution. However still the folder add event only fires once. Not sure what is the problem.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Linq;
using OutlookNS = Microsoft.Office.Interop.Outlook;
using Office = Microsoft.Office.Core;
using System.Net;
using System.Windows.Forms;
namespace OutlookAuditor
{
public partial class ThisAddIn
{
#region private variables
OutlookNS._NameSpace outNS;
OutlookNS.Explorer explorer;
string profileName = string.Empty;
List<SuperMailFolder> wrappedFolders = new List<SuperMailFolder>();
Logger logger = new Logger();
SuperMailFolder folderToWrap;
#endregion
private void ThisAddIn_Startup(object sender, System.EventArgs e)
{
try
{
OutlookNS.Application application = this.Application;
//Get the MAPI namespace
outNS = application.GetNamespace("MAPI");
//Get UserName
string profileName = outNS.CurrentUser.Name;
//Create a new outlook application
//I had to do this because my systems default mail box was ost file other just the below commented line is enough
//OutlookNS.MAPIFolder inbox = outNS.GetDefaultFolder(OutlookNS.OlDefaultFolders.olFolderInbox) as OutlookNS.MAPIFolder;
OutlookNS.MAPIFolder inbox;
OutlookNS.Folders folders = outNS.Folders;
OutlookNS.MAPIFolder selectedFolder = null;
if (folders.Count > 1)
{
List<string> folderNames = new List<string>();
foreach (OutlookNS.Folder folder in folders)
{
folderNames.Add(folder.Name);
}
using (selectMailBox frmSelect = new selectMailBox(folderNames))
{
if (DialogResult.OK == frmSelect.ShowDialog())
{
selectedFolder = folders[frmSelect.SelectedFolder];
}
}
}
else
{
selectedFolder = folders[1];
}
logger.SaveLog("Folder Selected " + selectedFolder.Name);
inbox = selectedFolder.Folders["Inbox"];//as OutlookNS.MAPIFolder;
//Create a super mail folder
folderToWrap = new SuperMailFolder(inbox, profileName);
wrappedFolders.Add(folderToWrap);
wrappedFolders.AddRange(folderToWrap.wrappedSubFolders);
//System.Runtime.InteropServices.Marshal.ReleaseComObject(inbox);
}
catch (Exception ex)
{
logger.WriteException(ex);
}
finally
{
}
}
private void ThisAddIn_Shutdown(object sender, System.EventArgs e)
{
}
#region VSTO generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InternalStartup()
{
this.Startup += new System.EventHandler(ThisAddIn_Startup);
this.Shutdown += new System.EventHandler(ThisAddIn_Shutdown);
}
#endregion
}
#region SuperMailItem object
class SuperMailItem
{
//local variable for avoiding GC invocation
OutlookNS.MailItem item;
string _profileName;
OutlookAuditor.Common.AuditItem auditItem;
string parentMailID;
string _folderName = string.Empty;
OutlookNS.MailItem replyItem;
Logger logger = new Logger();
//constructor that wraps mail item with required events
internal SuperMailItem(OutlookNS.MailItem MailItemToWrap, string profileName,string folderName)
{
try
{
item = MailItemToWrap as OutlookNS.MailItem;
_folderName = folderName;
if (item is OutlookNS.MailItem)
{
logger.SaveLog(item.Subject);
item.PropertyChange += MailItemToWrap_PropertyChange;
//item.PropertyChange += new OutlookNS.ItemEvents_10_PropertyChangeEventHandler(MailItemToWrap_PropertyChange);
((OutlookNS.ItemEvents_10_Event)item).Reply += SuperMailItem_Reply;
}
}
catch(Exception ex)
{
logger.WriteException(ex,"SuperMailItem Constructor");
}
}
void SuperMailItem_Reply(object Response, ref bool Cancel)
{
try
{
parentMailID = string.Empty;
replyItem = Response as OutlookNS.MailItem;
((OutlookNS.ItemEvents_10_Event)replyItem).Send += SuperMailItem_Send;
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
//this event is not firing
void SuperMailItem_Send(ref bool Cancel)
{
try
{
if (!Cancel)
{
createAuditItem();
auditItem.ActionDescription = "REPLY_SENT";
SaveLog();
}
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
//property change event- fires when any property of a mail item changes
void MailItemToWrap_PropertyChange(string Name)
{
try
{
createAuditItem();
//We are interested in UnRead property, if this property changes audit.
if (Name == "UnRead")
{
if (!item.UnRead)
{
auditItem.ActionDescription = "MAIL_READ";
}
else
{
auditItem.ActionDescription = "MAIL_UNREAD";
}
}
SaveLog();
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
void createAuditItem()
{
auditItem = new Common.AuditItem();
auditItem.ActionTimestamp = DateTime.Now;
auditItem.EntryID = item.EntryID;
auditItem.ProfileName = _profileName;
auditItem.ReceivedTimestamp = item.ReceivedTime;
auditItem.SystemIP = Helper.SystemIP();
auditItem.UserName = Helper.UserID();
auditItem.OriginalMailSentBy = item.Sender.Name;
auditItem.FolderName = _folderName;
auditItem.Subject = item.Subject;
}
void SaveLog()
{
Logger logger = new Logger();
logger.Save(auditItem);
}
}
#endregion
#region SuperMailFolder object
class SuperMailFolder
{
#region private variables
OutlookNS.MAPIFolder _wrappedFolder;
string _profileName;
List<SuperMailItem> wrappedItems = new List<SuperMailItem>();
public List<SuperMailFolder> wrappedSubFolders = new List<SuperMailFolder>();
string folderName = string.Empty;
Logger logger = new Logger();
#endregion
#region constructor
internal SuperMailFolder(OutlookNS.MAPIFolder folder, string profileName)
{
try
{
//assign it to local private master
_wrappedFolder = folder;
folderName = folder.Name;
_profileName = profileName;
//assign event handlers for the folder
_wrappedFolder.Items.ItemAdd +=Items_ItemAdd;
_wrappedFolder.Items.ItemRemove += Items_ItemRemove;
refreshItemList();
//Go through all the subfolders and wrap them as well
foreach (OutlookNS.MAPIFolder tmpFolder in _wrappedFolder.Folders)
{
logger.SaveLog("Wrapping folder " + tmpFolder.Name);
SuperMailFolder tmpWrapFolder = new SuperMailFolder(tmpFolder, _profileName);
wrappedSubFolders.Add(tmpWrapFolder);
wrappedSubFolders.AddRange(tmpWrapFolder.wrappedSubFolders);
}
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
#endregion
void Items_ItemRemove()
{
refreshItemList();
}
#region Handler of addition item into a folder
void Items_ItemAdd(object Item)
{
try
{
if (Item is OutlookNS.MailItem)
{
OutlookNS.MailItem item = Item as OutlookNS.MailItem;
wrappedItems.Add(new SuperMailItem(item, _profileName, folderName));
logger.SaveLog("Adding new item. New collection count:" + wrappedItems.Count.ToString());
OutlookAuditor.Common.AuditItem auditItem = new Common.AuditItem();
auditItem.ActionTimestamp = DateTime.Now;
auditItem.EntryID = item.EntryID;
auditItem.ProfileName = _profileName;
auditItem.ReceivedTimestamp = item.ReceivedTime;
auditItem.SystemIP = Helper.SystemIP();
auditItem.UserName = Helper.UserID();
auditItem.ActionDescription = "FOLDER_ADD";
auditItem.FolderName = folderName;
auditItem.OriginalMailSentBy = item.Sender.Name;
auditItem.Subject = item.Subject;
logger.Save(auditItem);
}
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
void refreshItemList()
{
try
{
wrappedItems.Clear();
wrappedItems = new List<SuperMailItem>();
logger.SaveLog("Wrapping items in " + folderName);
//Go through all the items and wrap it.
foreach (OutlookNS.MailItem item in _wrappedFolder.Items)
{
try
{
if (item is OutlookNS.MailItem)
{
OutlookNS.MailItem mailItem = item as OutlookNS.MailItem;
SuperMailItem wrappedItem = new SuperMailItem(mailItem, _profileName, folderName);
wrappedItems.Add(wrappedItem);
}
}
catch (Exception ex)
{
logger.WriteException(ex);
}
}
logger.SaveLog("Wrapped items in " + folderName + ":" + wrappedItems.Count.ToString());
}
catch(Exception ex)
{
logger.WriteException(ex);
}
}
#endregion
}
#endregion
static class Helper
{
public static string SystemIP()
{
string hostName = Dns.GetHostName();
string hostAddress = Dns.GetHostByName(hostName).AddressList[0].ToString();
return hostAddress;
}
public static string UserID()
{
return System.Security.Principal.WindowsIdentity.GetCurrent().Name;
}
}
}
回答1:
The following code is the problem:
_wrappedFolder.Items.ItemAdd +=Items_ItemAdd;
_wrappedFolder.Items.ItemRemove += Items_ItemRemove;
The object that fires the events must be alive - in your case you set up an event handler on an implicit variable returned from the _wrappedFolder.Items property - as soon as the GC releases that implicit variable, no events will fire. Declare the Items object on the class level to make sure it stays referenced and alive.
来源：https://stackoverflow.com/questions/42663830/outlook-2016-vsto-folder-add-event-fires-only-once