doing the same in vb.net -dllimport wingettext

[giorget]

As in precedent post i'm tryng do the same of this old post, importing wingettext

http://www.autoitscript.com/forum/lofivers...php?t10267.html

As this guy i always return a zero from the function.

this is the API declaration of c++

AU3_API void WINAPI AU3_WinGetText(const char *szTitle, /*[in,defaultvalue("")]*/const char *szText, char *szRetText, int nBufSize);

this how i import:

<DllImport("Autoitx3.dll")> _

Public Shared Sub AU3_WinGetText(ByVal strTitle As String, ByVal strText As String, ByRef returntxt As String, ByVal bufsize As Integer)

End Sub

and this is the way i call:

Dim test As String

AU3_WinGetText("Sapgui 640", "", test, 100)

maybe something wrong in nbufsize parameter? in the pasted post they speak about using a byte array as third parameter but i always receive a zero.

for test i've tried to use a normal call with referenced object (no dllimport) and works correctly

Any ideas?

thanks!

[piccaso]

if 'test' is a string and its 100 chars long before you pass it there is nothing wrong with it

try using cdecl and set charset to ansi.

edit: did you call AU3_Init() on startup?

Edited August 29, 2007 by piccaso

[BobK]

Try using an array of byte for the buffer.

Declare Sub AU3_WinGetText Lib "AutoItX3.dll" (ByVal Title As String, ByVal Txt As String, ByVal Buffer() As Byte, ByVal BufSize As Integer)

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

Dim buff(100) As Byte

Dim st As String = ""

Dim i As Integer = 0

AU3_WinGetText("Untitled", "", buff, 100)

Do While (buff(i) <> 0)

st = st + Chr(buff(i))

i = i + 1

Loop

MsgBox(st)

End Sub

[giorget]

Try using an array of byte for the buffer.

Declare Sub AU3_WinGetText Lib "AutoItX3.dll" (ByVal Title As String, ByVal Txt As String, ByVal Buffer() As Byte, ByVal BufSize As Integer)

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

Dim buff(100) As Byte

Dim st As String = ""

Dim i As Integer = 0

AU3_WinGetText("Untitled", "", buff, 100)

Do While (buff(i) <> 0)

st = st + Chr(buff(i))

i = i + 1

Loop

MsgBox(st)

End Sub

It works!!! thanks a lot....REally!!