go 调用dll char*传输

参考：http://www.voidcn.com/article/p-ofnbgvoa-bpv.html

https://stackoverflow.com/questions/53721215/syscall-mustloaddll-mustfindproc-throws-the-specified-procedure-could-not-be-fo

c++:

MYLIBDLL char* testchar(int plus1);
MYLIBDLL void greet(char *name);

      void greet(char *name)
      {
     	printf("Hello, %s!\n", name);
      }
      char* testchar(int plus1) {
     	char* str = "hello world111111";
     	return str;
      }
  
 

main.go代码：

      package main
      import (
      "syscall"
      "unsafe"
      "fmt"
      )
      import "C"
      func callDll() {
       dll := syscall.MustLoadDLL("hik_client.dll")
       procGreet := dll.MustFindProc("greet")
       procGreet.Call(uintptr(unsafe.Pointer(syscall.StringBytePtr("Cynhard11"))))
       procName := dll.MustFindProc("testchar")
       r, _, _ := procName.Call(1)
      // 获取C返回的指针。
      // 注意C返回的r为char*，对应的Go类型为*byte
       p := (*byte)(unsafe.Pointer(r))
      // 定义一个[]byte切片，用来存储C返回的字符串
       data := make([]byte, 0)
      // 遍历C返回的char指针，直到 '\0' 为止
      for *p != 0 {
       data = append(data, *p)  // 将得到的byte追加到末尾
       r += unsafe.Sizeof(byte(0))  // 移动指针，指向下一个char
       p = (*byte)(unsafe.Pointer(r))  // 获取指针的值，此时指针已经指向下一个char
       }
       name := string(data)  // 将data转换为字符串
       fmt.Printf("Hello, %s!\n", name)
      //var a = make([]byte, 256)
      //
      //
      //dll32 := syscall.NewLazyDLL("hik_client.dll")
      //fmt.Println("call dll:", dll32.Name)
      //GetPeopleName := dll32.NewProc("testchar")
      //
      //ret,_,err := GetPeopleName.Call(uintptr(unsafe.Pointer(&a)),2)
      //if err != nil {
      // fmt.Println(ret,a)
      // aaa := C.GoString(ret)
      // //C.free(unsafe.Pointer(cs))
      // //C.free(unsafe.Pointer(result))
      // //fmt.Println(aaa,a)
      //}
      //result, a, _ := g.Call(4)
      //fmt.Println("result is :", ret)
      }
      func main() {
       fmt.Println("start111111111!")
       callDll()
      //fmt.Println(C.add(2, 1))
      }
  
 

文章来源: blog.csdn.net，作者：网奇，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/jacke121/article/details/88381387