我正在创建一个无法与我的财务打印机通信的pos应用程序。因此，我决定将收据存储在文本文件中作为Json对象，并使用FileSystemWatch制作Windows Service应用程序以检查文件更新并将其转发到打印机。我正在使用第三方库与打印机进行通信。这是服务的代码：
Program.cs的
static void Main(string[] args)
{
var program = new Watcher();
if (Environment.UserInteractive)
{
program.Start();
}
else
{
ServiceBase.Run(new ServiceBase[]
{
program
});
}
//ServiceBase[] ServicesToRun;
//ServicesToRun = new ServiceBase[]
//{
// new Watcher()
//};
//ServiceBase.Run(ServicesToRun);
}
Watcher.cs
public partial class Watcher : ServiceBase
{
[DllImport("advapi32.dll", SetLastError = true)]
private static extern bool SetServiceStatus(IntPtr handle, ref ServiceStatus serviceStatus);
public static OICFiscalPrinter printer { get; set; }
[StructLayout(LayoutKind.Sequential)]
public struct ServiceStatus
{
public long dwServiceType;
public ServiceState dwCurrentState;
public long dwControlsAccepted;
public long dwWin32ExitCode;
public long dwServiceSpecificExitCode;
public long dwCheckPoint;
public long dwWaitHint;
};
public enum ServiceState
{
SERVICE_STOPPED = 0x00000001,
SERVICE_START_PENDING = 0x00000002,
SERVICE_STOP_PENDING = 0x00000003,
SERVICE_RUNNING = 0x00000004,
SERVICE_CONTINUE_PENDING = 0x00000005,
SERVICE_PAUSE_PENDING = 0x00000006,
SERVICE_PAUSED = 0x00000007,
}
public Watcher()
{
InitializeComponent();
}
public void CheckReceipt(object e, FileSystemEventArgs args)
{
printer = new OICFiscalPrinter();
var name = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
string text = null;
try
{
text = System.IO.File.ReadAllText(name + "\\Pictures\\test.txt");
var BasketList = JsonConvert.DeserializeObject<List<ItemsOnFacture>>(text);
printer.PortConfigString = "PortName=COM4;DataBits=8;Speed=9600;" +
"Parity = N; StopBits = 1; FlowControl = X;" +
"ReadTimeout = 6000;" +
"WriteTimeout = 500; UseReadBuffer = 1";
printer.Active = true;
var t = printer.Open();
if (!t) return;
printer.OpenReceipt();
foreach (var item in BasketList)
{
printer.ReceiptItem(item.ItemName, item.VatFee == 5 ? "B" : item.VatFee == 8 ? "A" : "D",
(decimal)item.PriceBrutto,
item.Amount, "unit", (decimal)item.PriceBruttoSum);
}
printer.CloseReceipt((decimal)BasketList.Sum(w => w.PriceBruttoSum),
(decimal)BasketList.Sum(w => w.PriceBruttoSum));
printer.Close();
File.Delete(name + "\\Pictures\\test.txt");
}
catch
{
}
}
public void Start()
{
//Start Logic here
var serviceStatus = new ServiceStatus
{
dwCurrentState = ServiceState.SERVICE_START_PENDING,
dwWaitHint = 100000
};
this.fileSystemWatcher1 = new System.IO.FileSystemWatcher();
((System.ComponentModel.ISupportInitialize)(this.fileSystemWatcher1)).BeginInit();
//
// fileSystemWatcher1
//
this.fileSystemWatcher1.EnableRaisingEvents = true;
var name = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
fileSystemWatcher1 = new FileSystemWatcher(name + "\\Pictures", "test.txt")
{
EnableRaisingEvents = true,
IncludeSubdirectories = false,
NotifyFilter = NotifyFilters.DirectoryName
};
SetServiceStatus(this.ServiceHandle, ref serviceStatus);
this.fileSystemWatcher1.Changed += new System.IO.FileSystemEventHandler(this.CheckReceipt);
((System.ComponentModel.ISupportInitialize)(this.fileSystemWatcher1)).EndInit();
// Update the service state to Running.
serviceStatus.dwCurrentState = ServiceState.SERVICE_RUNNING;
SetServiceStatus(this.ServiceHandle, ref serviceStatus);
}
protected override void OnStart(string[] args)
{
Start();
}
protected override void OnContinue()
{
}
protected override void OnStop()
{
}
private FileSystemWatcher fileSystemWatcher1;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Component Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
//
// Watcher
//
components = new System.ComponentModel.Container();
this.ServiceName = "WATTOFP";
}
#endregion
}
ProjectInstaller.cs
[RunInstaller(true)]
public class ProjectInstaller : System.Configuration.Install.Installer
{
public ProjectInstaller()
{
InitializeComponent();
}
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Component Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.serviceProcessInstaller1 = new System.ServiceProcess.ServiceProcessInstaller();
this.serviceInstaller1 = new System.ServiceProcess.ServiceInstaller();
//
// serviceProcessInstaller1
//
this.serviceProcessInstaller1.Account = System.ServiceProcess.ServiceAccount.LocalSystem;
this.serviceProcessInstaller1.Password = null;
this.serviceProcessInstaller1.Username = null;
//
// serviceInstaller1
//
this.serviceInstaller1.Description = "WATTO Fiscal Printer";
this.serviceInstaller1.DisplayName = "WATTO Fiscal Printer";
this.serviceInstaller1.ServiceName = "WATTOFP";
this.serviceInstaller1.StartType = System.ServiceProcess.ServiceStartMode.Automatic;
//
// ProjectInstaller
//
this.Installers.AddRange(new System.Configuration.Install.Installer[] {
this.serviceProcessInstaller1,
this.serviceInstaller1});
}
#endregion
private System.ServiceProcess.ServiceProcessInstaller serviceProcessInstaller1;
private System.ServiceProcess.ServiceInstaller serviceInstaller1;
}
问题在于，安装完成后，当我尝试运行服务时，它会启动并在警告出现时立即停止。如何运行服务并观察文件以进行更改？
答案 0 :(得分：0)
问题可能是默认情况下服务在系统帐户下运行。因此，用户文件夹不是您所期望的，并且没有文件。
通常在无法启动服务时，事件日志中应该出现异常错误。请在此处发布以获得进一步的帮助。