调试和测试 Windows 服务

Question

我有两个问题：

1. 我正在创建一个 Windows 服务，它将在每天凌晨 3 点 GMT 将数据库导出到一台服务器上并导入到另一台服务器上。我已经安装了我的服务并遵循了这个：https://msdn.microsoft.com/en-us/library/sd8zc8ha(v=vs.110).aspx。但是，我在服务代码中尝试过，它不允许我附加到该进程，并且还尝试在空白的 Visual Studio 页面中执行此操作（都作为管理员）并且不能，问题是当我运行我的服务由于某种原因停止了，所以如果可能的话，我需要一些关于如何测试和调试的想法，以确保服务正在做我想要的。

2. 我正在使用我的事件查看器告诉我一些错误，但这似乎随着时间的推移而代价高昂，但是我收到了一个错误，即：

   服务无法启动。 System.ArgumentException：在写入事件日志之前未设置源属性。 在 System.Diagnostics.EventLogInternal.WriteEntry（字符串消息，EventLogEntryType 类型，Int32 eventID，Int16 类别，Byte[] rawData） 在 System.Diagnostics.EventLog.WriteEntry（字符串消息） 在 C:\Dev\Projects\DBBackUpService\DBBackUpService\BackUpService.cs:line 27 中的 DBBackUpService.BackUpService.OnStart(String[] args) 在 System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(对象状态)

错误开始的代码在 OnStart 方法的开头：

System.Timers.Timer _timer = null;
    bool backUpRunning = false;
    public BackUpService()
    {
        InitializeComponent();
    }

    protected override void OnStart(string[] args)
    {
        
        BackUpLog.WriteEntry("Database Backup has begun.");
        _timer = new System.Timers.Timer { Interval = 3600000 };
        _timer.Elapsed += new System.Timers.ElapsedEventHandler(_timer_Elapsed);
        _timer.Start();
        Backup();
        
    }

    protected override void OnStop()
    {
        _timer.Stop();
        BackUpLog.WriteEntry("Database Backup has finished.");
    }

    public void _timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
        TimeSpan start = new TimeSpan(3, 0, 0);
        TimeSpan end = new TimeSpan(5, 0, 0);
        TimeSpan now = DateTime.Now.TimeOfDay;

        BackUpLog.WriteEntry("Checking if it's time to run the archive service and checking if the service is already running");


        if (backUpRunning)
            BackUpLog.WriteEntry("Service is already running");

        if ((now > start) && (now < end) && !backUpRunning)
        {
            BackUpLog.WriteEntry("Service is not already running and the time of day is valid to run the service.");
            try
            {
                backUpRunning = true;
                BackUpLog.WriteEntry("Initialising archive service");
                
            }
            catch (Exception ex)
            {
                logArchiveServiceError("The archive service failed. It will return to step 1 and try again: " + ex.Message);
            }
            finally
            {
                backUpRunning = false;
            }
        }

    }
    private void logArchiveServiceError(string errorMessage)
    {
        BackUpLog.WriteEntry(errorMessage, EventLogEntryType.Error);
        //Emailer.SendErrorAlertEmail("Archive Service Error", errorMessage, null, null);
    }

    private void logArchiveServiceInfo(string info)
    {
        BackUpLog.WriteEntry(info, EventLogEntryType.Information);
    }

TO ADD：创建此服务是为了将数据从一个数据库导出到另一个数据库。

Answer 1

根据提供的示例代码，您似乎没有初始化BackUpLog 的源代码。

//...other code removed for brevity
private const string logName = "Application";

protected override void OnStart(string[] args) {
    if (!EventLog.SourceExists(this.ServiceName)) {
        EventLog.CreateEventSource(this.ServiceName, logName);
    }
    //set the The source name by which the application is registered on the local computer.
    BackUpLog.Source = this.ServiceName;
    //The name of the log the source's entries are written to. 
    //Possible values include Application, System, or a custom event log. 
    BackUpLog.Log = logName;

    BackUpLog.WriteEntry("Database Backup has begun.");
    _timer = new System.Timers.Timer { Interval = 3600000 };
    _timer.Elapsed += new System.Timers.ElapsedEventHandler(_timer_Elapsed);
    _timer.Start();
    Backup();

}
//...other code removed for brevity