编译

exportgo.go

package main

import "C"

/*
   export PrintBye 的意思是将PrintBye方法通过PrintBye名暴露出去
*/
//export PrintBye
func PrintBye() {
   /*
      这里是只能用println
      不能用：log.Println()和fmt.Println()
   */
   println("From DLL: Bye!")
}

//export Sum
func Sum(a C.int, b C.int) C.int {
   return a + b
}

//export Sub
func Sub(a C.int, b C.int) C.int {
   return a - b
}

//export Hello
func Hello(a C.int, b C.int) C.int {
   return a * b
}

func main() {
   // Need a main function to make CGO compile package as C shared library
}

编译

>go build -buildmode=c-shared -o exportgo.dll exportgo.go

编译完成后，生成exportgo.dll和exportgo.h

调用

Called.go

package main

import "C"
import (
	"log"
	"syscall"
)

func main() {
	log.SetFlags(log.LstdFlags | log.Lshortfile)
	F4(50,30)
	F5(50,30)
	F6()
}
func F4(int1, int2 int) {
	log.Println(int1, int2)
	//引入dll文件方法1
	dll := syscall.MustLoadDLL("exportgo.dll")
	//使用完后要释放
	defer dll.Release()
	//调用dll的方法Sum
	proc := dll.MustFindProc("Sum")
	//使用sum函数，传递参数int1和int2
	call, u, err := proc.Call(uintptr(int1), uintptr(int2))
	//输出结果call
	log.Println(call)
	log.Println(u)
	log.Println(err)
}
func F5(int1, int2 int) {
	//引入dll文件方法2
	dll := syscall.NewLazyDLL("exportgo.dll")
	//调用dll的方法Sub
	proc := dll.NewProc("Sub")
	//使用Sub函数，传递参数int1和int2
	r, err, msg := proc.Call(uintptr(int1), uintptr(int2))
	//输出结果r
	log.Println(r)
	log.Println(err)
	log.Println(msg)
}
func F6() {
	//引入dll文件
	dll := syscall.NewLazyDLL("exportgo.dll")
	//调用dll的方法PrintBye
	proc := dll.NewProc("PrintBye")
	//调用dll的方法,不传递任何值
	r, err, msg := proc.Call()
	//输出结果r
	log.Println(r)
	log.Println(err)
	log.Println(msg)
}

执行结果

2022/03/26 14:48:00 Called.go:16: 50 30
2022/03/26 14:48:00 Called.go:26: 80
2022/03/26 14:48:00 Called.go:27: 8791506616320
2022/03/26 14:48:00 Called.go:28: The operation completed successfully.
2022/03/26 14:48:00 Called.go:38: 20
2022/03/26 14:48:00 Called.go:39: 8791503994880
2022/03/26 14:48:00 Called.go:40: The operation completed successfully.
From DLL: Bye!
2022/03/26 14:48:00 Called.go:50: 0
2022/03/26 14:48:00 Called.go:51: 8791503994880
2022/03/26 14:48:00 Called.go:52: The operation completed successfully.