leadergl
04-05-2005, 09:18
Ciao ragazzi,
ho un problema nel convertire una mia applicazione da VB6 a VB.NET o meglio ho un problema con un mio driver che serve ad interfacciarsi con una periferica USB in quanto il VB.NET mi restituisce errore sulla chiamata alla API CreateFile(...) per la connessione con un determinato apparecchio, vi posto il codice che mi da errore ed il tipo di errore:
Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As SECURITY_ATTRIBUTES, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function DeviceIoControl Lib "kernel32" (ByVal hDevice As Long, ByVal dwIoControlCode As Long, ByVal lpInBuffer As String, ByVal nInBufferSize As Long, ByVal lpOutBuffer As String, ByVal nOutBufferSize As Long, ByVal lpBytesReturned As Long, ByVal lpOverlapped As OVERLAPPED) As Long
Private Declare Function ReadFile Lib "kernel32.dll" (ByVal hFile As Long, ByRef lpBuffer As String, ByVal nNumberOfBytesToRead As Long, ByRef lpNumberOfBytesRead As Long, ByRef lpOverlapped As OVERLAPPED) As Long
Private Declare Function WriteFile Lib "kernel32.dll" (ByVal hFile As Long, ByRef lpBuffer As String, ByVal nNumberOfBytesToWrite As Long, ByRef lpNumberOfBytesWritten As Long, ByRef lpOverlapped As OVERLAPPED) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
'Costanti delle WinAPI
Private Const OPEN_EXISTING = 3
Private Const GENERIC_READ = &H80000000
Private Const GENERIC_WRITE = &H40000000
Private Const FILE_SHARE_READ = &H1
Private Const FILE_SHARE_WRITE = &H2
'Attributi di Sicurezza per la comunicazione
Private Structure SECURITY_ATTRIBUTES
Dim nLength As Long
Dim lpSecurityDescriptor As Long
Dim bInheritHandle As Long
End Structure
'Gestisce la sincronia della comunicazione
Private Structure OVERLAPPED
Dim Ternal As Long
Dim TernalHigh As Long
Dim Offset As Long
Dim OffsetHigh As Long
Dim hEvent As Long
End Structure
'Passo dalla Modalità Modem a quella Normal
Public Function SwitchToNormal(ByVal ModemGuID As String) As String
Dim DeviceHandle As Integer
Dim Sa As SECURITY_ATTRIBUTES
Dim OV As OVERLAPPED
Dim nShare As Integer
Dim ReceivedData As Integer 'Dati Ricevuti da USB
Dim Response As Integer
Dim ResponseString As String
nShare = FILE_SHARE_READ Or FILE_SHARE_WRITE
LenghtReceivedBuffer = 261
DeviceHandle = CreateFile("\\.\" & ModemGuID, GENERIC_WRITE, nShare, Sa, OPEN_EXISTING, 0, 0)
....
....
End Function
nel punto dove mi sono fermato mi da errore...:
An arithmetic, casting, or conversion operation in a checked context results in a overflow
In VB6 ovviamente funzionava tutto bene....ma evidentemente in VB.NET deve essere cambiato qualcosa...qualcuno sa come aiutartmi?
ho un problema nel convertire una mia applicazione da VB6 a VB.NET o meglio ho un problema con un mio driver che serve ad interfacciarsi con una periferica USB in quanto il VB.NET mi restituisce errore sulla chiamata alla API CreateFile(...) per la connessione con un determinato apparecchio, vi posto il codice che mi da errore ed il tipo di errore:
Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As SECURITY_ATTRIBUTES, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function DeviceIoControl Lib "kernel32" (ByVal hDevice As Long, ByVal dwIoControlCode As Long, ByVal lpInBuffer As String, ByVal nInBufferSize As Long, ByVal lpOutBuffer As String, ByVal nOutBufferSize As Long, ByVal lpBytesReturned As Long, ByVal lpOverlapped As OVERLAPPED) As Long
Private Declare Function ReadFile Lib "kernel32.dll" (ByVal hFile As Long, ByRef lpBuffer As String, ByVal nNumberOfBytesToRead As Long, ByRef lpNumberOfBytesRead As Long, ByRef lpOverlapped As OVERLAPPED) As Long
Private Declare Function WriteFile Lib "kernel32.dll" (ByVal hFile As Long, ByRef lpBuffer As String, ByVal nNumberOfBytesToWrite As Long, ByRef lpNumberOfBytesWritten As Long, ByRef lpOverlapped As OVERLAPPED) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
'Costanti delle WinAPI
Private Const OPEN_EXISTING = 3
Private Const GENERIC_READ = &H80000000
Private Const GENERIC_WRITE = &H40000000
Private Const FILE_SHARE_READ = &H1
Private Const FILE_SHARE_WRITE = &H2
'Attributi di Sicurezza per la comunicazione
Private Structure SECURITY_ATTRIBUTES
Dim nLength As Long
Dim lpSecurityDescriptor As Long
Dim bInheritHandle As Long
End Structure
'Gestisce la sincronia della comunicazione
Private Structure OVERLAPPED
Dim Ternal As Long
Dim TernalHigh As Long
Dim Offset As Long
Dim OffsetHigh As Long
Dim hEvent As Long
End Structure
'Passo dalla Modalità Modem a quella Normal
Public Function SwitchToNormal(ByVal ModemGuID As String) As String
Dim DeviceHandle As Integer
Dim Sa As SECURITY_ATTRIBUTES
Dim OV As OVERLAPPED
Dim nShare As Integer
Dim ReceivedData As Integer 'Dati Ricevuti da USB
Dim Response As Integer
Dim ResponseString As String
nShare = FILE_SHARE_READ Or FILE_SHARE_WRITE
LenghtReceivedBuffer = 261
DeviceHandle = CreateFile("\\.\" & ModemGuID, GENERIC_WRITE, nShare, Sa, OPEN_EXISTING, 0, 0)
....
....
End Function
nel punto dove mi sono fermato mi da errore...:
An arithmetic, casting, or conversion operation in a checked context results in a overflow
In VB6 ovviamente funzionava tutto bene....ma evidentemente in VB.NET deve essere cambiato qualcosa...qualcuno sa come aiutartmi?