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亚音速3活动记录删除/销毁引发异常

subsonic3 subsonic activerecord c#

TheVillageIdiot · 技术社区 · 15 年前

我有一个简单的表,其中有一个主键(标识)和几个 varchar 类型列。我尝试使用以下语法删除/销毁具有给定主键的记录:

SS3Test.DAL.TestClass.Destroy(x => x.TestId == _testId);

但当它被调用时,我会得到以下异常:

Failed to convert parameter value from a Func ` 2 to a Int32.

堆栈跟踪如下:

System.InvalidOperationException was unhandled
  Message="Failed to convert parameter value from a Func`2 to a Int32."
  Source="SubSonic.Core"
  StackTrace:
       at SubSonic.Query.SqlQuery.Execute()
       at SubSonic.Repository.SubSonicRepository`1.Delete(Object key, IDataProvider provider)
       at SubSonic.Repository.SubSonicRepository`1.Delete(Object key)
       at SS3Test.DAL.TestClass.Destroy(Func`2 expression) in E:\temp\SS3TEst\SS3Test.DAL\ActiveRecord.cs:line 2149
       at SS3Test.Model.TestClass.Delete(Int32 warrantyId, Boolean destroy) in E:\temp\SS3TEst\SS3Test.Model\TestClass.cs:line 84
       at SS3Test.GUI.FrmTestClass.btnDelete_Click(Object sender, EventArgs e) in E:\temp\SS3TEst\SS3Test.GUI\FrmTestClass.cs:line 72
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ButtonBase.WndProc(Message& m)
       at System.Windows.Forms.Button.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at SS3Test.GUI.Program.Main() in E:\temp\SS3TEst\SS3Test.GUI\Program.cs:line 21
       at System.AppDomain._nExecuteAssembly(Assembly 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)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.InvalidCastException
       Message="Failed to convert parameter value from a Func`2 to a Int32."
       Source="System.Data"
       StackTrace:
            at System.Data.SqlClient.SqlParameter.CoerceValue(Object value, MetaType destinationType)
            at System.Data.SqlClient.SqlParameter.GetCoercedValue()
            at System.Data.SqlClient.SqlParameter.Validate(Int32 index, Boolean isCommandProc)
            at System.Data.SqlClient.SqlCommand.BuildParamList(TdsParser parser, SqlParameterCollection parameters)
            at System.Data.SqlClient.SqlCommand.BuildExecuteSql(CommandBehavior behavior, String commandText, SqlParameterCollection parameters, _SqlRPC& rpc)
            at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
            at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
            at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe)
            at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
            at SubSonic.DataProviders.DbDataProvider.ExecuteQuery(QueryCommand qry)
            at SubSonic.Query.SqlQuery.Execute()
       InnerException: System.InvalidCastException
            Message="Object must implement IConvertible."
            Source="mscorlib"
            StackTrace:
                 at System.Convert.ChangeType(Object value, Type conversionType, IFormatProvider provider)
                 at System.Data.SqlClient.SqlParameter.CoerceValue(Object value, MetaType destinationType)

ps:-我有一个解决方法,从这个答案中,即从db中获取具有给定键的对象,然后对它调用delete。它起作用了,但我想知道为什么我会得到这个例外。另外,我使用的是SS 3.0.3(今天下载(2010年1月26日))。

2 回复 | 直到 15 年前

GC. 15 年前

它看起来像一个适当的bug,因为ActiveRecord销毁方法所依赖的子sonicRepository没有 Delete(expression) 超载。

我认为,如果您进入ActiveRecord.tt模板文件并找到:

    public static void Destroy(Func<<#=tbl.ClassName#>, bool> expression) {
        var repo = GetRepo();
        repo.Delete(expression);
    }

并更换 Delete 具有 DeleteMany 这将删除为给定表达式返回“真”的所有记录(如果使用主键,希望只有一个记录)。

气相色谱

Andy Jacobs 15 年前

我不熟悉库或函数,但错误消息意味着您正在传递一个函数作为参数,其中需要一个int32。实际上,您正在传递lambda函数(“=>”)作为要销毁的参数。所以首先要检查的是destroy是否真的想要一个函数,或者一个整数。

如果不是这样,请注意lambda函数正在重新调整bool(一个==比较的结果),但错误意味着需要一个int32。你可能需要把你的bool转换成int,你可以很容易地使用它?:这样的操作员:

x => ((x.TestId == _testId) ? 1 : 0)

当然,这两个答案都取决于销毁参数的实际期望值。