C#入门教程04.03：非托管dll调用

上一篇介绍了托管DLL调用，本部分介绍非托管，即非C#开发的DLL调用。

dll

先创建一个用于测试的dll，dll就是一个简单加法。

使用qt创建一个简单的dll。

#if defined(_MSC_VER) || defined(WIN64) || defined(_WIN64) || defined(__WIN64__) || defined(WIN32) \
    || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
#define Q_DECL_EXPORT __declspec(dllexport)
#define Q_DECL_IMPORT __declspec(dllimport)
#else
#define Q_DECL_EXPORT __attribute__((visibility("default")))
#define Q_DECL_IMPORT __attribute__((visibility("default")))
#endif

#if defined(SUMDLL_LIBRARY)
#define SUMDLL_EXPORT Q_DECL_EXPORT
#else
#define SUMDLL_EXPORT Q_DECL_IMPORT
#endif

extern "C" SUMDLL_EXPORT int sum(int a,int b){
    return a+b;
}

程序

新建一个终端程序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace sumprj
{
    class Program
    {
        static void Main(string[] args)
        {
        }
    }
}

添加引用

1 2	`[DllImport("sumdll.dll", EntryPoint = "sum", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Auto)] public extern static int sum(int a,int b);`

完整代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel;
using System.Data;
using System.Runtime.InteropServices;

namespace sumprj
{
    class Program
    {
        [DllImport("sumdll.dll", EntryPoint = "sum", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Auto)]
        public extern static int sum(int a,int b);
        static void Main(string[] args)
        {
            Int32 res = sum(1, 3);
            Console.WriteLine(res);
        }
    }
}