C#/vb calling C-written standard DLL

Get ready:

First Open VC + + 6.0 new project, select Win32 Dynamic link-library, named Stdlibrary

Create a new Library.cpp file with the following content

#include <stdio.h><windows.h>BOOL apientry DllMain (hmodule hmodule,                       DWORD  ul_ Reason_for_call,                       lpvoid lpreserved) {    return  TRUE;} HRESULT __stdcall  testadd (intintreturn i + j;}

The new text file is then named Export.def, which reads as follows

LIBRARY "Stdlibrary"

Exports
Testadd @1

Compile project Get StdLibrary.dll

1 VB Call StdLibrary.dll

New Standard EXE project, drag interface,

Right-click on the code and write the following code

Private Declare FunctionTestaddLib "StdLibrary.dll"(ByValInX as Long,ByValIny as Long) as LongPrivate SubCmdcaclute_click ()DimX as LongDimY as LongDimResult as Longx=txtx.texty=Txty.textresult=testadd (x, y) txtresult.text=resultEnd Sub

Then use VB to generate EXE, drag the StdLibrary.dll to the project in the compiled directory, run can, call success.

Note: VB calls the third-party DLL, the debugging process Lib "StdLibrary.dll" if not the absolute path will be error, do not know whether VB Bug, as long as the generation of EXE after the run will not error

2 C # Call StdLibrary.dll

Write the following code and drag the StdLibrary.dll to the Debug/release directory

usingSystem;usingSystem.Collections.Generic;usingSystem.Text;usingSystem.Runtime.InteropServices;namespacecsharpcallclibrary{classProgram {[DllImport ("StdLibrary.dll", CallingConvention =Callingconvention.stdcall)] Public Static extern intTestadd (intXinty); Static voidMain (string[] args) {            intx =1, y =2, result=0; Result=testadd (x, y); Console.WriteLine ("{0} + {1} = {2}", X,y,result);        Console.read (); }    }}

Run compile-generated EXE, this call succeeds

C#/vb calling C-written standard DLL