Create wrapper for c++ imported function in C#,Vb.net

Asked Oct 30 '17 at 12:30

Active Nov 01 '17 at 19:16

Viewed 41 times

I have got c++ function with export looking like this:

extern "C" __declspec(dllexport) LPCWSTR Function(void)

But cannot get answer from it in vb.net. Always get error that memory is corrupted.

I can alredy execute imported code like this:

extern "C" __declspec(dllexport) int Function2(wchar_t*)

Can some one help with this?

Already found solution.

For my template it looks like:

    <DllImport(DllName)>
    Protected Shared Function Function() As IntPtr
    End Function

    Public Shared Function AliasForFunction() As String
        Return Marshal.PtrToStringAuto(Function())
    End Function

edited Nov 01 '17 at 19:16

asked Oct 30 '17 at 12:30

Gotemcity FY

Can you show the code you have tried in C# & vb.net - then maybe we can let you know how to correct it. – PaulF Oct 30 '17 at 12:39
Is the c++ actually returning a LPCWSTR? – jdweng Oct 30 '17 at 12:39
Yes, LPCWSTR. The test code in c++ is working. Looks like Label3->Caption=finction1(); – Gotemcity FY Oct 30 '17 at 12:45
How is the lifetime of the returned string managed? – David Heffernan Oct 30 '17 at 13:51
An `LP(C)WSTR` is usually mapped to a `StringBuilder`. I made a table of some of the most common types here: https://stackoverflow.com/a/46547553/3740093 – Visual Vincent Oct 30 '17 at 14:38
1

@VisualVincent No. `LPCWSTR` is mapped to `string`, with the appropriate encoding. Here we have a function return value, and `StringBuilder` can't be used in that setting anyway. – David Heffernan Oct 30 '17 at 16:21
@DavidHeffernan : You're right, my mistake. – Visual Vincent Oct 30 '17 at 16:57

Create wrapper for c++ imported function in C#,Vb.net

0 Answers0