C# 调用C++的dll，通过DllImport方式。 from http://www.cnblogs.com/xiaokang088/archive/2011/04/08/2009673.html

C# 调用C++的dll，通过DllImport方式。

以下例子包含以下几种参数传递方式：

传递string、Int、Int数组、结构体、结构体数组。

比较懒，没写注释，呵呵，各位辛苦了。

demo在这里

C++ Dll 如下：

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// dllmain.cpp : Defines the entry point for the DLL application.

#include "stdafx.h"

#include <stdio.h>

#include <tchar.h>

 

BOOL APIENTRY DllMain( HMODULE hModule,

                       DWORD  ul_reason_for_call,

                       LPVOID lpReserved

                     )

{

    switch (ul_reason_for_call)

    {

    case DLL_PROCESS_ATTACH:

    case DLL_THREAD_ATTACH:

    case DLL_THREAD_DETACH:

    case DLL_PROCESS_DETACH:

        break;

    }

    return TRUE;

}

 

struct PersonInfo

{

    int id;

    wchar_t name;

};

 

 

struct StudentInfo

{

    int id;

    wchar_t name[100];

};

 

 

int Add(int para1,int para2)

{

    return para1+para2;

};

 

int TestStruct(struct PersonInfo* person)

{

    person->id=10;

    return 0;

};

 

int TestStructArray(struct  PersonInfo   persons[5] )

{

    persons[0].id=11;

    persons[0].name = L'a';

 

    persons[1].id=22;

    persons[1].name = L'b';

 

    persons[2].id=33;

    persons[2].name = L'c';

 

    persons[3].id=44;

    persons[3].name = L'd';

 

    persons[4].id=55;

    persons[4].name = L'e';

 

    return 0;

};

 

int TestStructArray2(struct  StudentInfo   students[3] )

{

    students[0].id=11;

    wcscpy(students[0].name,L"aaaaaaa");

     

    TCHAR szMsg[200] = {0};

    _stprintf_s(szMsg, 200, _T("size of PersonInfo2:%d"), sizeof(StudentInfo));

    ::OutputDebugString(szMsg);

 

    students[1].id=22;

    wcscpy(students[1].name,L"bbbb");

 

    students[2].id=33;

    wcscpy(students[2].name,L"ccc");

 

    return 0;

};

 

 

 

 

int TestIntArr(int tt[5])

{

    tt[0]=0;

    tt[1]=1;

    tt[2]=2;

    tt[3]=3;

    tt[4]=4;

 

    return 0;

}

 

int TestString(LPTSTR buffer, DWORD size)

{

    wcscpy_s(buffer,size,L"eststsetwet");

    return 0;

}

C++ def文件如下：

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LIBRARY "Win32Dll"

 

EXPORTS

     Add

     TestStruct

     TestStructArray

     TestStructArray2

     TestIntArr

     TestString

C# 调用代码如下：

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/// <summary>

/// Interaction logic for Window1.xaml

/// </summary>

public partial class Window1 : Window

{

    public Window1()

    {

        InitializeComponent();

        Loaded += new RoutedEventHandler(button1_Click);

    }

 

    private void button1_Click(object sender, RoutedEventArgs e)

    {

        int num1 = 0, num2 = 0;

        if (!string.IsNullOrEmpty(textBox1.Text) && !string.IsNullOrEmpty(textBox2.Text))

        {

            num1 = Convert.ToInt32(textBox1.Text);

            num2 = Convert.ToInt32(textBox2.Text);

 

            int ret = DllTest.Add(Convert.ToInt32(textBox1.Text), Convert.ToInt32(textBox2.Text));

            textBlock3.Text = ret.ToString();

        }

 

        PersonInfo p = new PersonInfo();

        DllTest.TestStruct(ref p);

 

        //int dd = p.id;

 

        int[] intArray = new int[5];

        DllTest.TestIntArr(intArray);

        Debug.WriteLine(intArray);

 

        PersonInfo[] ps = new PersonInfo[5];

        DllTest.TestStructArray(ps);

 

        int t = Marshal.SizeOf(new StudentInfo());

        //  var t = sizeof(PersonInfo2);

 

        StudentInfo[] ps2 = new StudentInfo[3];

        DllTest.TestStructArray2(ps2);

 

        short[] name = ps2[0].name;

        string ret13 = new string(name.Where(o => o != 0).Select(o => (char)o).ToArray());

 

        char[] chars = new char[100];

 

        StringBuilder builder = new StringBuilder(256);

        DllTest.TestString(builder, 256);

    }

 

}

 

 

public class DllTest

{

    [DllImport("Win32Dll.dll", EntryPoint = "Add")]

    public static extern Int32 Add(int a, int b);

 

    [DllImport("Win32Dll.dll", EntryPoint = "TestStruct")]

    public static extern Int32 TestStruct(ref PersonInfo person);

 

    [DllImport("Win32Dll.dll", EntryPoint = "TestStructArray")]

    public static extern Int32 TestStructArray([In, Out]  PersonInfo[] persons);

 

    [DllImport("Win32Dll.dll", EntryPoint = "TestStructArray2")]

    public static extern Int32 TestStructArray2([In, Out]  StudentInfo[] students);

 

    [DllImport("Win32Dll.dll", EntryPoint = "TestIntArr")]

    public static extern Int32 TestIntArr([In, Out] int[] intArray);

 

    [DllImport("Win32Dll.dll", EntryPoint = "TestString")]

    public static extern Int32 TestString([MarshalAs(UnmanagedType.LPTStr)]StringBuilder buffer, Int32 length);

}

 

[ComVisible(false), StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]

public struct PersonInfo

{

    public int id;

    public char name;

}

 

[StructLayout(LayoutKind.Sequential)]

public struct StudentInfo

{

    public int id;

 

    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 100)]

    public short[] name;

}