Converting VB6 to C#

Hi Experts,

I have a VB6 program that I am currently converting to C# and I am having issues interfacing to a particular method in an existing unmanaged dll.

All calls to the dll so far have worked perfectly, but this is the only method that passes a reference to a struct and is the only one I am having trouble with.

How would I write my dll import and call the method?


C++ dll Method declaration

int _stdcall getVBArrayStrValues(LPSTR tagName, LPSTR itemName, 
						short firstElmNo, short lastElmNo, LPSAFEARRAY FAR * ppsaStringRead)

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VB Declaration of the dll

Public Declare Function getVBArrayStrValues Lib "FILENAME.dll" _
                                        (ByVal lpTagName As String, _
                                         ByVal lpItemName As String, _
                                         ByVal firstElmNo As Integer, _
                                         ByVal lastElmNo As Integer, _
                                         ByRef stringRead() As vbStringRead) As Integer

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Type/Struct Definition

Type vbStringRead
    readStatus As Integer
    valueStr As String
End Type

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VB call to the dll

ret = getVBArrayStrValues(tag, item, i1, i2, strRead())

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My best guess for the C# Code:

ret = getVBArrayStrValues(tag, item, i1, i2, ref strRead);

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public struct vbStringRead
        {
            public int readStatus;
            public string valueStr;
        }

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[DllImport("FILENAME.dll")]
        public static extern int getVBArrayStrValues(string lpTagName, string lpItemName, int firstElmNo, int lastElmNo, ref vbStringRead[] stringRead);

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