Question

所以当我尝试将连接字符串放在app.config文件中时，我遇到了一个问题。在此之后我得到以下MySQL错误：

MySql.Data.MySqlClient.MySqlException was unhandled
ErrorCode=-2147467259
HResult=-2147467259
Message=Unable to connect to any of the specified MySQL hosts.
Number=1042
Source=MySql.Data
StackTrace:
   at MySql.Data.MySqlClient.NativeDriver.Open()
   at MySql.Data.MySqlClient.Driver.Open()
   at MySql.Data.MySqlClient.Driver.Create(MySqlConnectionStringBuilder settings)
   at MySql.Data.MySqlClient.MySqlPool.GetPooledConnection()
   at MySql.Data.MySqlClient.MySqlPool.TryToGetDriver()
   at MySql.Data.MySqlClient.MySqlPool.GetConnection()
   at MySql.Data.MySqlClient.MySqlConnection.Open()
   at SalesKicker2.Connector.connectionOpen(Boolean open) in F:\C# Projects\SalesKicker2\SalesKicker2\Connector.cs:line 38
   at SalesKicker2.gebruikerGegevens.btnNext_Click(Object sender, RoutedEventArgs e) in F:\C# Projects\SalesKicker2\SalesKicker2\gebruikerGegevens.xaml.cs:line 38
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.Controls.Primitives.ButtonBase.OnClick()
   at System.Windows.Controls.Button.OnClick()
   at System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonUp(MouseButtonEventArgs e)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.ReRaiseEventAs(DependencyObject sender, RoutedEventArgs args, RoutedEvent newEvent)
   at System.Windows.UIElement.OnMouseUpThunk(Object sender, MouseButtonEventArgs e)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
   at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at SalesKicker2.App.Main() in F:\C# Projects\SalesKicker2\SalesKicker2\obj\Debug\App.g.cs:line 0
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext, String[] activationCustomData)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssemblyDebugInZone()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

我发现这非常奇怪，因为我之前使用过以下行：

"Server=myremoteserverip; Port=3306; Database=mydb; Uid=myusername; Pwd=mypass"

这在我的VPS之前完美无缺。这个服务器显然不是localy托管的。我查了很多文章，仍然没有找到任何好的解决方案。我在app.config文件中使用连接字符串的原因是您无法使用反编译器找到它。这就是我将我的连接字符串放在app.config中的方式：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup> 
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" />
</startup>
<appSettings>
  <add key="connection" value="Server=ip; Port=3306; Database=db; Uid=usr; Pwd=pass"/>
</appSettings>
</configuration>

我使用密钥是因为connectionString只尝试连接到本地数据库。显然不应该发生这种情况。这就是我在C＃代码中使用连接字符串的方式：

public static string conString = ConfigurationManager.AppSettings["connection"];
public static MySqlConnection SalesKicker = new MySqlConnection(conString);

你可以看到错误告诉我一个bool。这个bool会触发SalesKicker.open（）事件，如下所示：

    public static void connectionOpen(bool open)
    {
        if (open)
            SalesKicker.Open();
        if (!open)
            SalesKicker.Close();
    }

SalesKicker.Open（）;抛出异常。我真的很困惑，并且真的不知道我在这里做错了什么。有人可以指出我的错误。我真的想知道如何正确地做到这一点

注：

我的MySQL服务器确实正常运行

应用程序突然无法连接到我的数据库服务器

0 个答案: