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我一直在使用pcsc-sharp庫的小型智能卡掃描程序應用程序。作爲控制檯應用程序運行時，應用程序正常工作，代碼如下：PCSC.InvalidContextException作爲Windows服務運行時
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;
using System.IO;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Drawing.Printing;
using System.Net;
using System.Net.Sockets;
using System.Data.SqlClient;
using System.Threading;
using System.IO.Ports;
using System.Text.RegularExpressions;
using System.Speech.Synthesis;
using System.Diagnostics;
using PCSC;
using System.Media;
namespace MeterTestingApplication
{
class Program
{
static void Main(string[] args)
{
// Retrieve the names of all installed readers.
string[] readerNames;
using (var context = new SCardContext())
{
context.Establish(SCardScope.System);
readerNames = context.GetReaders();
context.Release();
}
if (readerNames == null || readerNames.Length == 0)
{
Console.WriteLine("There are currently no readers installed.");
return;
}
// Create a monitor object with its own PC/SC context.
// The context will be released after monitor.Dispose()
using (var monitor = new SCardMonitor(new SCardContext(), SCardScope.System))
{
// Point the callback function(s) to the anonymous & static defined methods below.
monitor.CardInserted += (sender, args0) => DisplayEvent("CardInserted", args0);
//monitor.CardRemoved += (sender, args0) => DisplayEvent("CardRemoved", args0);
//monitor.Initialized += (sender, args0) => DisplayEvent("Initialized", args0);
//monitor.StatusChanged += StatusChanged;
monitor.MonitorException += MonitorException;
monitor.Start(readerNames);
// Keep the window open
Console.ReadLine();
}
}
private static void DisplayEvent(string eventName, CardStatusEventArgs unknown)
{
Console.WriteLine(">> {0} Event for reader: {1}", eventName, unknown.ReaderName);
Console.WriteLine("ATR: {0}", BitConverter.ToString(unknown.Atr ?? new byte[0]));
Console.WriteLine("State: {0}\n", unknown.State);
//Works fine here
}
private static void StatusChanged(object sender, StatusChangeEventArgs args)
{
//Console.WriteLine(">> StatusChanged Event for reader: {0}", args.ReaderName);
//Console.WriteLine("ATR: {0}", BitConverter.ToString(args.Atr ?? new byte[0]));
//Console.WriteLine("Last state: {0}\nNew state: {1}\n", args.LastState, args.NewState);
}
private static void MonitorException(object sender, PCSCException ex)
{
Console.WriteLine("Monitor exited due an error:");
Console.WriteLine(SCardHelper.StringifyError(ex.SCardError));
}
}
}
然而，當試圖運行它作爲Windows服務 - 允許卡掃描更新數據庫 - 事件永遠不會觸發並且它在服務啓動時似乎崩潰。事件日誌顯示PCSC.InvalidContextException錯誤。該服務的代碼差不多完全相同，但這裏是示例。
using System;
using System.Diagnostics;
using System.ServiceProcess;
using System.Timers;
using System.Configuration;
using System.Linq;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.IO;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Drawing.Printing;
using System.Threading;
using System.Speech.Synthesis;
using System.IO.Ports;
using System.Text.RegularExpressions;
using PCSC;
using System.Media;
using log4net;
namespace CardScannerService
{
public partial class CardScanner : ServiceBase
{
private ILog logger;
private SCardContext context;
private string[] readerNames;
private SCardMonitor monitor;
private static System.Timers.Timer aTimer;
public CardScanner()
{
InitializeComponent();
}
static void Main()
{
ServiceBase.Run(new CardScanner());
}
//
// Start Service
//
protected override void OnStart(string[] args)
{
aTimer = new System.Timers.Timer();
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = (1000 * 60 * 60 * 24); // Once a day; 1000ms * 60s * 60m * 24h
aTimer.Enabled = true;
//// Entry point
using (context = new SCardContext())
{
context.Establish(SCardScope.System);
readerNames = context.GetReaders();
context.Release();
}
if (readerNames == null || readerNames.Length == 0)
{
EventLog.WriteEntry("CardReaderService", "There are currently no readers installed.");
return;
}
// Create a monitor object with its own PC/SC context.
// The context will be released after monitor.Dispose()
using (monitor = new SCardMonitor(new SCardContext(), SCardScope.System))
{
// Point the callback function(s) to the anonymous & static defined methods below.
monitor.CardInserted += (sender, args0) => DisplayEvent("CardInserted", args0);
//monitor.CardRemoved += (sender, args0) => DisplayEvent("CardRemoved", args0);
//monitor.Initialized += (sender, args0) => DisplayEvent("Initialized", args0);
//monitor.StatusChanged += StatusChanged;
monitor.MonitorException += MonitorException;
monitor.Start(readerNames);
// Keep the window open
//Console.ReadLine();
}
logger.InfoFormat("CardScannerService Started at {0}", DateTime.Now.ToLongTimeString());
}
//
// Stop Service
//
protected override void OnStop()
{
logger.InfoFormat("CardScannerService Stopped at {0}", DateTime.Now.ToLongTimeString());
}
//
// Execute timed event every hour and half hour
//
void OnTimedEvent(object source, ElapsedEventArgs e)
{
// Card scanner service entry point for timed event - any cleanup code can go here
}
private static void DisplayEvent(string eventName, CardStatusEventArgs unknown)
{
EventLog.WriteEntry("CardReaderService", ">> " + eventName + "v Event for Reader: " + unknown.ReaderName);
EventLog.WriteEntry("CardReaderService", "ATR: " + BitConverter.ToString(unknown.Atr ?? new byte[0]));
EventLog.WriteEntry("CardReaderService", "State: " + unknown.State);
//Not firing
}
private static void StatusChanged(object sender, StatusChangeEventArgs args)
{
//Console.WriteLine(">> StatusChanged Event for reader: {0}", args.ReaderName);
//Console.WriteLine("ATR: {0}", BitConverter.ToString(args.Atr ?? new byte[0]));
//Console.WriteLine("Last state: {0}\nNew state: {1}\n", args.LastState, args.NewState);
}
private static void MonitorException(object sender, PCSCException ex)
{
EventLog.WriteEntry("CardReaderService", "Monitor exited due an error:");
EventLog.WriteEntry("CardReaderService", SCardHelper.StringifyError(ex.SCardError));
}
}
}
我已經剝離出來的實際的數據庫邏輯，似乎做工精細，我相信努力要麼釋放上下文變量或顯示器連接到智能卡，當它崩潰。
還必須聲明，我已嘗試將服務從開始使用本地系統帳戶更改爲使用本地服務，以防萬一它是某種訪問權限錯誤。
如果有人可以告訴我哪裏出錯，我會非常感謝幫助。我在與PC/SC合作方面相對較新，現在似乎已經在這個項目中遇到了困難。
UPDATE
我現在已經解決了這個問題;原來Windows服務不喜歡使用語句。變量放置在塊的末尾，因此上下文變得無效。
使用塊已被註釋掉，變量的聲明是在它們的位置完成的。 OnStart方法的新代碼如下：
protected override void OnStart(string[] args)
{
logger = LogManager.GetLogger(this.GetType().Name);
aTimer = new System.Timers.Timer();
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = (1000 * 60 * 60 * 24); // Once a day; 1000ms * 60s * 60m * 24h
aTimer.Enabled = true;
// Entry point
//using (context = new SCardContext())
//{
context = new SCardContext();
context.Establish(SCardScope.System);
readerNames = context.GetReaders();
context.Release();
//}
if (readerNames == null || readerNames.Length == 0)
{
EventLog.WriteEntry("CardReaderService", "There are currently no readers installed.");
return;
}
// Create a monitor object with its own PC/SC context.
// The context will be released after monitor.Dispose()
//using (monitor = new SCardMonitor(new SCardContext(), SCardScope.System))
//{
monitor = new SCardMonitor(new SCardContext(), SCardScope.System);
// Point the callback function(s) to the anonymous & static defined methods below.
monitor.CardInserted += (sender, args0) => DisplayEvent("CardInserted", args0);
//monitor.CardRemoved += (sender, args0) => DisplayEvent("CardRemoved", args0);
//monitor.Initialized += (sender, args0) => DisplayEvent("Initialized", args0);
//monitor.StatusChanged += StatusChanged;
monitor.MonitorException += MonitorException;
monitor.Start(readerNames);
// Keep the window open
//Console.ReadLine();
//}
logger.InfoFormat("CardScannerService Started at {0}", DateTime.Now.ToLongTimeString());
}
希望此信息可以幫助其他人。
嗨Jayse它不適合我，我刪除使用，但仍ame錯誤 – 2017-05-03 10:04:42