验证从VB.net发送的Outlook电子邮件是否已实际发送

Imports Outlook = Microsoft.Office.Interop.Outlook

Public Sub SendEmail()
    Dim outlookApp As New Outlook.Application()
    Dim mailItem As Outlook.MailItem = outlookApp.CreateItem(Outlook.OlItemType.olMailItem)
    
    ' 设置邮件的相关属性
    mailItem.Subject = "邮件主题"
    mailItem.Body = "邮件内容"
    mailItem.To = "收件人邮箱地址"
    
    ' 发送邮件
    mailItem.Send()
    
    ' 关闭Outlook应用程序
    outlookApp.Quit()
End Sub

Public Function IsEmailSent() As Boolean
    Dim outlookApp As New Outlook.Application()
    Dim sentItemsFolder As Outlook.MAPIFolder = outlookApp.GetNamespace("MAPI").GetDefaultFolder(Outlook.OlDefaultFolders.olFolderSentMail)
    
    ' 获取已发送邮件夹中的最新一封邮件
    Dim lastSentEmail As Outlook.MailItem = sentItemsFolder.Items.GetLast()
    
    ' 检查邮件的发送状态
    If lastSentEmail IsNot Nothing AndAlso lastSentEmail.Sent Then
        ' 邮件已发送
        Return True
    Else
        ' 邮件未发送
        Return False
    End If
    
    ' 关闭Outlook应用程序
    outlookApp.Quit()
End Function