为什么vc++提示不允许使用类型名？

Question

如题。
下面是代码

#include <stdio.h>
#include <iostream>
#include <Windows.h>
#include <Mmsystem.h>
#include <joystickapi.h>
//#include <myjoy.h>
#pragma comment(lib, "WinMM.lib")



int main() {
    UINT num,IF;
    BOOL ID;
    int i;
    JOYINFO joyinfo;
    /*struct joyinfo_tag {
        UINT wXpos;
        UINT wYpos;
        UINT wZpos;
        UINT wButtons;
    } JOYINFO, * PJOYINFO, * NPJOYINFO, * LPJOYINFO;*/

    //joyGetPos(JOYSTICKID1, &joyinfo);
    //IF = JOY_BUTTON1;
    //JOYINFO joyinfo;
    num = joyGetNumDevs();
    printf("%u\n", num);
    Sleep(1000);
    ID = joyGetPos(JOYSTICKID1, &joyinfo);
    if (ID == JOYERR_NOERROR) {
        printf("Have a joy\n");
        Sleep(1000);
    }
    else {
        printf("the joy is null\n");
        Sleep(1000);
    }
    typedef struct alphe{};
    //listen();
    //printf("%u", IF);
    for (;;) {
        /*joyGetPos(JOYSTICKID1, &joyinfo);
        IF = JOY_BUTTON1;
        if (IF == 0) {
            printf("the button1 is down\n");
            Sleep(1000);
        }
        else {
            printf("the button1 is not down\n");
            Sleep(1000);
        }*/
        if (num > 0)
        {
            //joySetThreshold(JOYSTICKID1, 10000);
            //joySetCapture((HWND)this->winId(), JOYSTICKID1, NULL, TRUE);
            IF = joyinfo_tag.wButtons;
            if (IF == JOY_BUTTON1) {
                printf("the Button1 is down\n");
            }
            else if (IF == JOY_BUTTON2) ｛
                printf("the Button2 is down\n");
            }
            
        }
        
    }
    
}

然后在第56行 IF = joyinfo_tag.wButtons; 这个赋值语句中的结构体 joyinfo_tag 被vc++说成“不允许使用类型名”
下面是图片：

![img]( https://img-mid.csdnimg.cn/release/static/image/mid/ask/387627892826128.png https://img-mid.csdnimg.cn/release/static/image/mid/ask/387627892826128.png '无标题.png‘
希望各位能多多帮助
（与joystick有关，需要头文件请私信）

Answer 1

joyinfo_tag是结构体名称，你应该改为该结构体的对象名称！望采纳！