Outlook加载项无法将mailitem添加到自定义文件夹中

Question

I want to take mails from inbox and sentbox folders, compare their subjects and if they match, put it all into a new custom folder. Here's the code so far:

Outlook.MAPIFolder inBox = (Outlook.MAPIFolder)
        this.Application.ActiveExplorer().Session.GetDefaultFolder
        (Outlook.OlDefaultFolders.olFolderInbox);

// I also have made this for the sentBox folder

            string userName = (string)this.Application.ActiveExplorer()
                .Session.CurrentUser.Name;
            Outlook.MAPIFolder customFolder = null;

                customFolder = (Outlook.MAPIFolder)inBox.Folders.Add(userName,
                    Outlook.OlDefaultFolders.olFolderInbox);

                inBox.Folders[userName].Display();

// This is the custom folder in which i wish to place the matching mails

        for (int i = 1; i <= sentboxFolder.Items.Count; i++)
        {
            outboxItem =  sentboxFolder.Items[i];


            for (int a = 1; a <= inBox.Items.Count; a++)
            {
               inboxItem = inBox.Items[a];

                if ("RE: " + outboxItem.Subject == inboxItem.Subject)
                {

                    customFolder.Items.Add(inboxItem);

// Here I loop through the inbox and outbox folders and if the subjects match I want to add the inbox part to the custom folder.

I have 3 questions: 1. Is there a way to put both matching mails into one folder ? 2. I know there should be a smarter way to this aside from comparing subjects, Can anyone help how to use conversation ID here? 3. I get an exception at the last line, that it cannot add inbox item into custom folder because it's not an actual object instance. Where should I instantiate mailitem to fix this ?

Thanks in advance.

Answer 1

Firstly, do not use multiple dot notation, especially in a loop - cache the Items collection before entering the loop.

Secondly, do not just loop through all items in a folder looking for a match - use Items.Find.

That being said, you can use MailItem.Move(OtherFolder) . If you want to preserve the original item, use MailItem.Copy (returns new item), then move it to the target folder.