how to wrap some dll functions from VC6

[yyf]

Hi, everyone I am using a dll developped in VC6. There are some functions I don't know how to wrap it in C#. 1. one function's parameter use self defined type, type definition is like this: #ifndef LPLONG typedef long far *LPLONG; /* 32 bit */ #endif 2. one function's parameter use 'BOOL *' 3. one function's parameter use 'char *' 4. one function's return value use 'char *' 5. one function's parameter use a structure 6. one function's parameter use a structure * How shall I deal with these? Thanks in advance.

[Heath Stewart]

1. ref int 2. ref bool 3. [MarshalAs(UnmanagedType.LPStr)]string 4. [return: MarshalAs(UnmanagedType.LPStr)]string 5. Just pass the struct, but see the docs for the StructLayoutAttribute 6. ref _YourStruct_ All these - escept for 3 and 4 - are value types so you use ref or out (the latter if you don't need to pass any initial value to your functions). Don't use ref or out with a string because it is already a reference type. Both char* and char[] are strings since a string is only an array of characters. Since you're using char and not wchar_t (or TCHAR), you must marshal them as ANSI strings.

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[yyf]

How about void *? Thanks.

[Heath Stewart]

IntPtr

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