Question

我正在尝试在.NET 3.5中编写一个小型Windows服务，如果你是“C：\ demofolder”中的新文件，每隔10美元检查一次，然后发送电子邮件。到目前为止，我在下面的代码中已经到了这里，然后在Public Sub New（）

中出现错误

Imports System
Imports System.Timers
Imports System.ServiceProcess
Public Class TestMyService

    '  A timer that controls how frequenty the example writes to the
    '  event log.
    Private serviceTimer As Timer

    Public Sub New()

        '  Set the ServiceBase.ServiceName property.
        ServiceName = "TestMyService Service"

        '  Configure the level of control available on the service.
        CanStop = True
        CanPauseAndContinue = True
        CanHandleSessionChangeEvent = True

        '  Configure the service to log important events to the
        '  Application event log automatically.
        AutoLog = True

    End Sub

    Protected Overrides Sub OnStart(ByVal args() As String)
        ' Add code here to start your service. This method should set things
        ' in motion so your service can do its work.
    End Sub

    Protected Overrides Sub OnStop()
        ' Add code here to perform any tear-down necessary to stop your service.
    End Sub

Public Shared Sub Main()

    '  Create an instance of the TestMyService class that will write
    '  an entry to the Application event log.  Pass the object to the
    '  shared ServiceBase.Run method.
    ServiceBase.Run(New TestMyService)

End Sub


End Class

我收到以下错误消息：

  在'mcWinService.TestMyService'中多次声明
Sub Main'：mcWinService.TestMyService.Main（），mcWinService.TestMyService.Main（）

Public Shared Sub Main（）'具有多个具有相同签名的定义。

设计器生成的类型'mcWinService.TestMyService'中的Public Sub New（）'应该调用InitializeComponent方法。

Answer 1

尝试移动

来自Public Shared Sub Main（）
的
ServiceBase.Run（New TestMyService）

到

受保护的覆盖Sub OnStart

然后删除Public Shared Sub Main（）

此外，删除Public Sub New（），因为您可以从“Property Windows”中设置这些属性。 F7从代码切换到设计师视图。

更新1：文件夹监视器的Windows服务示例

Imports System.Net.Mail
Imports System.Net
Imports System.Timers
Imports System.IO

Public Class DemoFolderMonitor

    Private Shared timer As System.Timers.Timer
    Private Shared timerInterval As Integer

    Protected Overrides Sub OnStart(ByVal args() As String)
        ' Add code here to start your service. This method should set things
        ' in motion so your service can do its work.

        '  Use the EventLog object automatically configured by the
        '  ServiceBase class to write to the event log.
        'EventLog.WriteEntry(String.Format("DemoFolderMonitor Service starting."))

        ' Set the Interval  (1sec = 1000 milliseconds).
        timerInterval = 2000
        timer = New System.Timers.Timer(timerInterval)
        EventLog.WriteEntry("DemoFolderMonitor Service starting.")

        ' Hook up the Elapsed event for the timer.
        AddHandler timer.Elapsed, AddressOf WatchFolder

        timer.Interval = timerInterval
        timer.Enabled = True

    End Sub

    Protected Overrides Sub OnStop()
        ' Add code here to perform any tear-down necessary to stop your service.
        EventLog.WriteEntry("DemoFolderMonitor Service stopping...")

    End Sub

    Protected Sub WatchFolder()

        Dim watcher As New FileSystemWatcher
        watcher.Path = "C:\Demo\"

        watcher.NotifyFilter = (NotifyFilters.LastAccess Or NotifyFilters.LastWrite Or NotifyFilters.FileName Or NotifyFilters.DirectoryName)

        'watch all file types.
        watcher.Filter = "*.*"
        ' Add event handlers.
        AddHandler watcher.Changed, AddressOf OnChanged
        AddHandler watcher.Created, AddressOf OnChanged
        AddHandler watcher.Deleted, AddressOf OnChanged
        AddHandler watcher.Renamed, AddressOf OnRenamed

        ' Begin watching.
        watcher.EnableRaisingEvents = True

    End Sub

    'Define the event handlers.
    Private Shared Sub OnChanged(ByVal source As Object, ByVal e As FileSystemEventArgs)
        ' Specify what is done when a file is changed, created, or deleted.
        Dim changeLog = "File: " & e.FullPath & " " & " | Action: " & e.ChangeType.ToString
        WriteChangeLog(changeLog)

    End Sub

    Private Shared Sub OnRenamed(ByVal source As Object, ByVal e As RenamedEventArgs)
        ' Specify what is done when a file is renamed.
        Dim changeLog = "File" & e.OldFullPath & " " & "renamed to" & " " & e.FullPath
        WriteChangeLog(changeLog)

    End Sub

    'Custom action. You can either send an e-mail or write change to local file
    'In this example I write change to local file
    Private Shared Sub WriteChangeLog(ByVal changeLog As String)

        'Create a text file and write the change log to the text file
        Dim filename As String = DateTime.Now.ToString("hh-mm-ss") & ".txt"
        Dim writer As StreamWriter
        writer = File.CreateText("C:\ChangeLog\" & filename)
        writer.WriteLine("Datetime Log  at {0} Log Message: {1}", DateTime.Now.ToString("MMM-dd-yyyy @ hh:mm:ss tt"), changeLog)
        writer.Close()

    End Sub

End Class

进一步相关阅读检查：

振作！

Answer 2

听起来你在另一个项目文件中有另一个Main方法。在项目范围内搜索单词Main并查看是否可以找到它。

您还可以通过进入项目的属性对话框并选择TestMyService作为启动对象而不是Sub Main来修复该错误。

Windows服务

2 个答案: