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Convert to VB.NET

Hello,

Recently, I converted my VB6 app to VB.NET. I got the standard upgrade
messages and fixed them so now I can run my app. I have noticed, though,
that some of the library functions will not work in .NET, namely:

CreateFile
LockFile
UnlockFile
CloseHandle

declared as

Public Declare Auto Function CreateFile Lib "kernel32.d ll" Alias
"CreateFile A" (ByVal lpFileName As String, ByVal dwDesiredAccess As
Int32, ByVal dwShareMode As Int32, ByRef lpSecurityAttri butes As IntPtr,
ByVal dwCreationDispo sition As Int32, ByVal dwFlagsAndAttri butes As
Int32, ByVal hTemplateFile As IntPtr) As IntPtr
Public Declare Auto Function LockFile Lib "kernel32.d ll" (ByVal hFile
As IntPtr, ByVal dwFileOffsetLow As Int32, ByVal dwFileOffsetHig h As
Int32, ByVal nNumberOfBytesT oLockLow As Int32, ByVal
nNumberOfBytesT oLockHigh As Int32) As Int32
Public Declare Auto Function UnlockFile Lib "kernel32.d ll" (ByVal
hFile As IntPtr, ByVal dwFileOffsetLow As Int32, ByVal dwFileOffsetHig h
As Int32, ByVal nNumberOfBytesT oUnlockLow As Int32, ByVal
nNumberOfBytesT oUnlockHigh As Int32) As Int32
Public Declare Auto Function CloseHandle Lib "kernel32.d ll" (ByVal
hObject As IntPtr) As Boolean

How do I fix this problem?

Thanks,
Andrew
Nov 21 '05 #1
5 2242

"Andrew Clark" <la*****@hotmai l.com> wrote in message
news:1128102107 .693793a8f2ca80 434a2a9538de42f 1ce@teranews...
Hello,

Recently, I converted my VB6 app to VB.NET. I got the standard upgrade
messages and fixed them so now I can run my app. I have noticed, though,
that some of the library functions will not work in .NET, namely:

CreateFile
LockFile
UnlockFile
CloseHandle

The conversion process does not do a good job with Win32 functions. You
should either replace the Win32 API calls with the built-in functionality
from the .net frametwork, or go research the proper vb.net Win32 api
declares (www.pinvoke.net).

David
Nov 21 '05 #2
Hi Andrew,

In CreateFile declaration change ~ ByRef lpSecurityAttib utes As IntPtr ~
either to ~ ByVal lpSecurityAttri butes As IntPtr ~ or to ~ ByRef
lpSecurityAttri butes As SECURITY_ATTRIB UTES ~.

Also please post code in which you use these functions.

Roman

"Andrew Clark" <la*****@hotmai l.com> ñîîáùèë/ñîîáùèëà â íîâîñòÿõ
ñëåäóþùåå: news:1128102107 .693793a8f2ca80 434a2a9538de42f 1ce@teranews...
Hello,

Recently, I converted my VB6 app to VB.NET. I got the standard upgrade
messages and fixed them so now I can run my app. I have noticed, though, that some of the library functions will not work in .NET, namely:

CreateFile
LockFile
UnlockFile
CloseHandle

declared as

Public Declare Auto Function CreateFile Lib "kernel32.d ll" Alias
"CreateFile A" (ByVal lpFileName As String, ByVal dwDesiredAccess As
Int32, ByVal dwShareMode As Int32, ByRef lpSecurityAttri butes As IntPtr, ByVal dwCreationDispo sition As Int32, ByVal dwFlagsAndAttri butes As
Int32, ByVal hTemplateFile As IntPtr) As IntPtr
Public Declare Auto Function LockFile Lib "kernel32.d ll" (ByVal hFile As IntPtr, ByVal dwFileOffsetLow As Int32, ByVal dwFileOffsetHig h As
Int32, ByVal nNumberOfBytesT oLockLow As Int32, ByVal
nNumberOfBytesT oLockHigh As Int32) As Int32
Public Declare Auto Function UnlockFile Lib "kernel32.d ll" (ByVal
hFile As IntPtr, ByVal dwFileOffsetLow As Int32, ByVal dwFileOffsetHig h As Int32, ByVal nNumberOfBytesT oUnlockLow As Int32, ByVal
nNumberOfBytesT oUnlockHigh As Int32) As Int32
Public Declare Auto Function CloseHandle Lib "kernel32.d ll" (ByVal
hObject As IntPtr) As Boolean

How do I fix this problem?

Thanks,
Andrew

Nov 21 '05 #3
"Dragon" <no@spam.please > wrote in news:Oa2kj9exFH A.3256
@TK2MSFTNGP09.p hx.gbl:
Hi Andrew,

In CreateFile declaration change ~ ByRef lpSecurityAttib utes As IntPtr ~
either to ~ ByVal lpSecurityAttri butes As IntPtr ~ or to ~ ByRef
lpSecurityAttri butes As SECURITY_ATTRIB UTES ~.

Also please post code in which you use these functions.

Roman


I made the suggested change. hFile still gets -1 (and I am sure the file
exists). Here is a snippet where I use CreateFile,

Dim hFile As IntPtr
hFile = IntPtr.Zero

hFile = CreateFile( _
"test03.txt ", _
GENERIC_READ, _
0, _
IntPtr.Zero, _
OPEN_EXISTING, _
FILE_ATTRIBUTE_ NORMAL, _
IntPtr.Zero)

This will always set hFile to -1. The values of the constants are listed
below,

GENERIC_READ 1179785
OPEN_EXISTING 3
FILE_ATTRIBUTE_ NORMAL 128

I am not finding a whole lot of help on the 'net for this :(

Andrew
Nov 21 '05 #4
"Andrew Clark" <la*****@hotmai l.com> schrieb:

In addition to the other replies:
Public Declare Auto Function CreateFile Lib "kernel32.d ll" Alias
"CreateFile A"
Remove the 'Alias "CreateFile A"' alias.
Public Declare Auto Function LockFile Lib "kernel32.d ll" (ByVal hFile
Remove 'Auto'.
Public Declare Auto Function UnlockFile Lib "kernel32.d ll" (ByVal
Remove 'Auto'.
Public Declare Auto Function CloseHandle Lib "kernel32.d ll" (ByVal
hObject As IntPtr) As Boolean


Remove 'Auto'.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>
Nov 21 '05 #5
> GENERIC_READ 1179785

Ah, now I see...
It's

~
Const GENERIC_READ As Integer = &H80000000
~

Roman
Nov 21 '05 #6

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