1:  Imports System.Data.Common

   2:  Imports System.Data.Entity.Infrastructure.Interception

   3:  Imports System.Data.SqlClient

   4:  Imports System.Reflection

   5:   

   6:  Namespace Log1

   7:   

   8:      Public Class InterceptorTransientErrors

   9:          Inherits DbCommandInterceptor

  10:   

  11:          Private _counter As Integer = 0

  12:          Private _logger As ILogger = New Logger1()

  13:   

  14:          Public Overrides Sub ReaderExecuting(ByVal command As DbCommand, ByVal interceptionContext As DbCommandInterceptionContext(Of DbDataReader))

  15:              Dim throwTransientErrors As Boolean = False

  16:              If command.Parameters.Count > 0 AndAlso command.Parameters(0).Value.ToString() = "%Throw%" Then

  17:                  throwTransientErrors = True

  18:                  command.Parameters(0).Value = "%an%"

  19:                  command.Parameters(1).Value = "%an%"

  20:              End If

  21:   

  22:              If throwTransientErrors AndAlso _counter < 4 Then

  23:                  _logger.Information("Returning transient error for command: {0}", command.CommandText)

  24:                  _counter += 1

  25:                  interceptionContext.Exception = CreateDummySqlException()

  26:              End If

  27:          End Sub

  28:   

  29:          Private Function CreateDummySqlException() As SqlException

  30:              Dim sqlErrorNumber = 20

  31:              Dim sqlErrorCtor = GetType(SqlError).GetConstructors(BindingFlags.Instance Or BindingFlags.NonPublic).Single(Function(c) c.GetParameters().Count() = 7)

  32:              Dim sqlError = sqlErrorCtor.Invoke(New Object() {sqlErrorNumber, CByte(0), CByte(0), "", "", "", 1})

  33:              Dim errorCollection = Activator.CreateInstance(GetType(SqlErrorCollection), True)

  34:              Dim addMethod = GetType(SqlErrorCollection).GetMethod("Add", BindingFlags.Instance Or BindingFlags.NonPublic)

  35:              addMethod.Invoke(errorCollection, {sqlError})

  36:              Dim sqlExceptionCtor = GetType(SqlException).GetConstructors(BindingFlags.Instance Or BindingFlags.NonPublic).Single(Function(c) c.GetParameters().Count() = 4)

  37:              Dim sqlException = CType(sqlExceptionCtor.Invoke(New Object() {"Dummy", errorCollection, Nothing, Guid.NewGuid()}), SqlException)

  38:              Return sqlException

  39:          End Function

  40:      End Class

  41:   

  42:  End Namespace