c# - SQLite C# WPF读取错误

Question

我是 c# 的新手，我尝试读取 .db 文件，我已在以下链接的帮助下将 ADO.NET 2.0 Provider for SQLite 添加到我的项目中:http://sourceforge.net/projects/sqlite-dotnet2/ .但是我在运行时遇到错误，我无法理解这个问题。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Data;
using System.Diagnostics;
using System.Data.SQLite;


namespace WpfApplication1.Screens
{
    /// <summary>
    /// Interaction logic for FirstScreen.xaml
    /// </summary>
    public partial class FirstScreen : UserControl, ISwitchable
    {

        public FirstScreen()
        {
            InitializeComponent();

            Debug.WriteLine("Send to debug output.");


                        String connString = "Data Source=C:\\projects.db";
            using (SQLiteConnection conn = new SQLiteConnection(connString))
            {
                StringBuilder query = new StringBuilder();
                query.Append("SELECT App ");
                query.Append("FROM Alqueva ");

                using (SQLiteCommand cmd = new SQLiteCommand(query.ToString(), conn))
                {
                    conn.Open();
                    using (SQLiteDataReader dr = cmd.ExecuteReader())
                    {
                        while (dr.Read())
                        {
                           Debug.WriteLine(dr.GetValue(0) + " " + dr.GetValue(1) + " " + dr.GetValue(2));
                        }
                    }
                }
            }
            //Console.ReadLine();

        }

    }
}

错误:

System.Windows.Markup.XamlParseException was unhandled
  Message='The invocation of the constructor on type 'WpfApplication1.MainWindow' that matches the specified binding constraints threw an exception.' Line number '3' and line position '9'.
  Source=PresentationFramework
  LineNumber=3
  LinePosition=9
  StackTrace:
       at System.Windows.Markup.XamlReader.RewrapException(Exception e, IXamlLineInfo lineInfo, Uri baseUri)
       at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri)
       at System.Windows.Markup.WpfXamlLoader.LoadBaml(XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri)
       at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream)
       at System.Windows.Application.LoadBamlStreamWithSyncInfo(Stream stream, ParserContext pc)
       at System.Windows.Application.LoadComponent(Uri resourceLocator, Boolean bSkipJournaledProperties)
       at System.Windows.Application.DoStartup()
       at System.Windows.Application.<.ctor>b__1(Object unused)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.DispatcherOperation.InvokeImpl()
       at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
       at System.Threading.ExecutionContext.runTryCode(Object userData)
       at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Windows.Threading.DispatcherOperation.Invoke()
       at System.Windows.Threading.Dispatcher.ProcessQueue()
       at System.Windows.Threading.Dispatcher.WndProcHook(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 MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.Dispatcher.InvokeImpl(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.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
       at System.Windows.Application.RunDispatcher(Object ignore)
       at System.Windows.Application.RunInternal(Window window)
       at System.Windows.Application.Run(Window window)
       at System.Windows.Application.Run()
       at WpfApplication1.App.Main() in C:\Users\User\documents\visual studio 2010\Projects\WpfApplication1\WpfApplication1\obj\x86\Debug\App.g.cs:line 0
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.IO.FileLoadException
       Message=Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information.
       Source=WpfApplication1
       StackTrace:
            at WpfApplication1.Screens.FirstScreen..ctor()
            at WpfApplication1.MainWindow..ctor() in C:\Users\User\documents\visual studio 2010\Projects\WpfApplication1\WpfApplication1\MainWindow.xaml.cs:line 17
       InnerException: 

Answer 1

你的 Sqlite 连接必须是这样的:

Data Source=name.db;Version=3;

Connection strings for SQLite

在App.config中添加

<startup useLegacyV2RuntimeActivationPolicy="true">
  <supportedRuntime version="v4.0"/>
</startup>