Attempted to read or write protected memory. This is often an indication that other m

[mafc]

Estoy intentando leer los datos devueltos por una consulta, pero obtengo este error en el read del FbDataReader. Este es el código que utilizo.


Friend FbConnection As FirebirdSql.Data.FirebirdClient.FbConnection

Friend SQL As String
Friend dbDataAdapter As FirebirdSql.Data.FirebirdClient.FbDataAdapter
Friend dbDataSet As New Data.DataSet
Friend dr As FbDataReader
..................

FbConnection = New FirebirdSql.Data.FirebirdClient.FbConnection(Caden aConexion)
dbDataSet.Clear()

If (FbConnection.State = ConnectionState.Closed) Then
FbConnection.Open()
End If

........

SQL = "select CATE_ID from T_CATEGORIAS WHERE CATE_NOMBRE='@v_categoria'"

Dim prm As New FbParameter
Dim cmd As FbCommand



cmd = New FbCommand(SQL, FbConnection, Transaccion)
cmd.Parameters.Add("@v_categoria", FbDbType.VarChar).Value = "Cat1"
cmd.CommandType = CommandType.Text

dr = cmd.ExecuteReader()
While dr.Read --------- Fail in this line
dr.Item("CATE_ID").ToString()
End While


dr.Close()


Gracias