void MciFunction (char *FilePath)
{
    FILE *fp = fopen ("MusicName.txt" , "r");
    if (!fp)
        return ;
    char FileName[260];
    char cmd[260];
    MCIDEVICEID dev = 0;
    MCI_OPEN_PARMSA open;
    DWORD n;

    MCI_PLAY_PARMS play;
    MCI_BREAK_PARMS br;
    play.dwCallback = NULL;
    play.dwFrom = 0;
    br.nVirtKey = 0x61;
    br.dwCallback = NULL;

    fgets (FileName , 260 , fp);
    FileName[strlen (FileName) - 1] = '\0';
    sprintf (cmd , "%s%s" , FilePath , FileName);
    open.lpstrDeviceType = NULL;
    open.lpstrElementName = cmd;
//    printf ("%s" , cmd);
    n = mciSendCommandA (NULL , MCI_OPEN ,
        MCI_OPEN_ELEMENT | MCI_WAIT | MCI_OPEN_SHAREABLE , (DWORD)(PVOID)&open);
    if (n == 0)
    {
        dev = open.wDeviceID;
    }
    else
    {
        puts ("失败");
        return;
    }
        
    n=mciSendCommand (dev , MCI_BREAK , MCI_BREAK_KEY ,(DWORD)(PVOID)&br);
//    printf ("%ld" , n);
    mciSendCommand (dev , MCI_PLAY , MCI_WAIT  , (DWORD)(PVOID)&play );   
}
我将“1”键设为中断音乐播放的按键，但为什么运行时要按两次音乐才中断啊？

为啥会这样呢，按“1”键将wait功能中断后，如果不再按一次的话，wait的功能在整个程序中都是处于中断状态。如果在播放一首歌曲，我想换下一首的时候，按了“1”键，停止了歌曲，但是后面的歌曲也一个也播放不了了。
我想实现的功能是：播放一个文件夹内的所有MP3文件，在播放的过程中，我可以通过一个按键来切换下一首歌曲。如果在我不切换歌曲的情况下，播放完一首歌曲之后，它会自动播放下一首。
有没有什么办法实现这个功能啊？
我写了下面的代码，改来改去的，但是就是不行。难受……
求指教、求指点……
#define _CRT_SECURE_NO_WARNINGS
# include <stdio.h>
# include <conio.h>
# include <windows.h>
# include <stdlib.h>
# include <string.h>
# include <io.h>
# include <errno.h>
# pragma comment (lib , "WINMM.LIB")

void GetFileName (char *FilePath , char * FileNameExtension)
{
    FILE * fp = fopen ("MusicName.txt" , "w+");
    if (!fp)
        return ;
    _finddata_t Info;
    char cmd[MAX_PATH];
    sprintf (cmd , "%s%s" , FilePath , FileNameExtension);
    long hFind;
    hFind = _findfirst (cmd , &Info);
    fputs (Info.name , fp);
    if (hFind == -1)
    {
        puts ("失败");
        return ;
    }
    while (!_findnext (hFind , &Info))
    {
        fputs ("\n" , fp);
        puts (Info.name);
        fputs (Info.name , fp);
    }
    fputs ("\n" , fp);
    fclose (fp);
    _findclose (hFind);
}

void MciFunction (char *FilePath , char *FileName)
{
   
//    char FileName[260];
    char cmd[260];
   
    MCIDEVICEID dev = 0;
    MCI_OPEN_PARMSA open;
    DWORD n;

    MCI_PLAY_PARMS play;
    MCI_BREAK_PARMS br;

//    while (fgets (FileName , 260 , fp) != NULL)
//    {
    open.lpstrAlias = "mysong";
    play.dwCallback = NULL;
    play.dwFrom = 0;
    br.nVirtKey = VK_DOWN;
    br.dwCallback = NULL;

   
    FileName[strlen (FileName) - 1] = '\0';
    sprintf (cmd , "%s%s" , FilePath , FileName);
    open.lpstrDeviceType = NULL;
    open.lpstrElementName = cmd;
    printf ("%s\n" , cmd);
    n = mciSendCommandA (NULL , MCI_OPEN ,
        MCI_OPEN_ELEMENT | MCI_WAIT | MCI_OPEN_SHAREABLE , (DWORD)(PVOID)&open);
    if (n == 0)
    {
        dev = open.wDeviceID;
    //    printf ("%d\n" , open.dwCallback);
    }
    else
    {
        puts ("失败");
        return;
    }
//    MCI_STATUS_PARMS status;
//    status.dwItem = MCI_STATUS_POSITION;
//    printf ("%d\n", dev);   

    n=mciSendCommand (dev , MCI_BREAK , MCI_BREAK_KEY ,(DWORD)(PVOID)&br);

    mciSendCommand (dev , MCI_PLAY , MCI_WAIT , (DWORD)(PVOID)&play );

//    mciSendCommand (dev , MCI_STATUS , MCI_STATUS_ITEM , (DWORD)(PVOID)&status);
//    printf ("%d\n" , status.dwReturn);
   
    MCI_GENERIC_PARMS close;
    close.dwCallback = NULL;
    mciSendCommand (dev , MCI_CLOSE , 0 , (DWORD)(PVOID)&close);
    //}
    return ;
}

int main (void)
{
    char FilePath[MAX_PATH] = "C:\\Users\\yutang\\Desktop\\music\\";
    char FileNameExtension[32] = "*.mp3";
//    gets (FilePath);
//    gets (FileNameExtension);
    char FileName[260];
    FILE *fp = fopen ("MusicName.txt" , "r");
    if (!fp)
        return 0;
    GetFileName (FilePath , FileNameExtension);
    while (fgets (FileName , 260 , fp) != 0)
    {
        MciFunction (FilePath , FileName);
    }
    fclose (fp);
    return 0;
}

[此贴子已经被作者于2017-10-22 18:53编辑过]

好的， 我在去查查看看这方面的知识

#define _CRT_SECURE_NO_WARNINGS
# include <stdio.h>
# include <conio.h>
# include <windows.h>
# include <stdlib.h>
# include <string.h>
# include <io.h>
# include <errno.h>
# pragma comment (lib , "WINMM.LIB")

void Error (MCIERROR err)
{
    char buf[260];
    mciGetErrorStringA (err , buf , sizeof (buf));
    printf ("\t%d\t%s\n " , err , buf);
}

 void SetDown (void)
   {
      // Simulate a key press
         keybd_event( VK_DOWN,
                      0x5000,
                      KEYEVENTF_EXTENDEDKEY,
                      0 );

      // Simulate a key release
          keybd_event( VK_DOWN,
                      0x5000,
                      KEYEVENTF_KEYUP,
                      0);
 }

void GetFileName (char *FilePath , char * FileNameExtension)
{
    FILE * fp = fopen ("MusicName.txt" , "w+");
    if (!fp)
        return ;
    _finddata_t Info;
    char cmd[MAX_PATH];
    sprintf (cmd , "%s%s" , FilePath , FileNameExtension);
    long hFind;
    hFind = _findfirst (cmd , &Info);
    fputs (Info.name , fp);
    if (hFind == -1)
    {
        puts ("失败");
        return ;
    }
    while (!_findnext (hFind , &Info))
    {
        fputs ("\n" , fp);
        puts (Info.name);
        fputs (Info.name , fp);
    }
    fputs ("\n" , fp);
    fclose (fp);
    _findclose (hFind);
}

void MciFunction (char *FilePath , char *FileName)
{
   
//    char FileName[260];
    char cmd[260];
   
    MCIDEVICEID dev = 0;
    MCI_OPEN_PARMSA open;
    DWORD err;

    MCI_PLAY_PARMS play;
    MCI_BREAK_PARMS br;

//    while (fgets (FileName , 260 , fp) != NULL)
//    {
//    open.lpstrAlias = "mysong";
    play.dwCallback = NULL;
    play.dwFrom = 0;
    br.nVirtKey = VK_DOWN;
    br.hwndBreak = NULL;
    br.dwCallback = NULL;
     
   
    FileName[strlen (FileName) - 1] = '\0';
    sprintf (cmd , "%s%s" , FilePath , FileName);
    open.lpstrDeviceType = NULL;
    open.lpstrElementName = cmd;
    printf ("%s\n" , cmd);
    err = mciSendCommandA (NULL , MCI_OPEN ,
        MCI_OPEN_ELEMENT | MCI_WAIT | MCI_OPEN_SHAREABLE , (DWORD)(PVOID)&open);
    if (err)
    {
        Error (err);
        return;
    }
    dev = open.wDeviceID;
//    MCI_STATUS_PARMS status;
//    status.dwItem = MCI_STATUS_POSITION;

    err = mciSendCommand (dev , MCI_BREAK , MCI_BREAK_KEY ,(DWORD)(PVOID)&br);
    if (err)
    {
        Error (err);
        return;
    }
    err = mciSendCommand (dev , MCI_PLAY , MCI_WAIT , (DWORD)(PVOID)&play );
    SetDown ();
    Sleep (1000);
    if (err)
    {
        Error (err);
        return;
    }
//    mciSendCommand (dev , MCI_STATUS , MCI_STATUS_ITEM , (DWORD)(PVOID)&status);
//    printf ("%d\n" , status.dwReturn);
   
    MCI_GENERIC_PARMS close;
    close.dwCallback = NULL;
    mciSendCommand (dev , MCI_CLOSE , 0 , (DWORD)(PVOID)&close);
    //}
}

int main (void)
{
    char FilePath[MAX_PATH] = "C:\\Users\\yutang\\Desktop\\music\\";
    char FileNameExtension[32] = "*.mp3";
//    gets (FilePath);
//    gets (FileNameExtension);
    char FileName[260];
    FILE *fp = fopen ("MusicName.txt" , "r");
    if (!fp)
        return 0;
    GetFileName (FilePath , FileNameExtension);
    while (fgets (FileName , 260 , fp) != 0)
    {
        MciFunction (FilePath , FileName);
    }
    fclose (fp);
    return 0;
}
我加了一个函数，void SetDown (void)，有那么一点意思了，但还是有些问题。总是隔一首播放一首，不知道是怎么回事。
MCI_BREAK_HWND 这个句柄是怎么来的，怎么获取这个参数啊 。
我在上面查了下，HWND  hwndBreak 只是介绍了这个成员代表了什么，但是怎么获取，怎么用就不知道了。

[此贴子已经被作者于2017-10-23 03:04编辑过]

#define _CRT_SECURE_NO_WARNINGS
# include <stdio.h>
# include <conio.h>
# include <windows.h>
# include <stdlib.h>
# include <string.h>
# include <io.h>
# include <errno.h>
# pragma comment (lib , "WINMM.LIB")

void KeyboardEvent (int VirKey)//这个函数不能用
{
    HANDLE hIn = GetStdHandle (STD_INPUT_HANDLE);
    DWORD UL;
    INPUT_RECORD inrec;
    ReadConsoleInput (hIn , &inrec , 1 , &UL);
    if (inrec.EventType == KEY_EVENT)
    {
        if (inrec.Event.KeyEvent.wVirtualKeyCode == VirKey
            )
            BlockInput (1);//这个函数一旦运行，鼠标，键盘都被锁定，无法控制。
        else
            BlockInput (0);
    }
}

void Error (MCIERROR err)
{
    char buf[260];
    mciGetErrorStringA (err , buf , sizeof (buf));
    printf ("\t%d\t%s\n " , err , buf);
}

 void SetDown (void)
{

    // Simulate a key press
        keybd_event( VK_DOWN,
                    0x5000,
                    KEYEVENTF_EXTENDEDKEY|0,
                    0 );

    // Simulate a key release
        keybd_event( VK_DOWN,
                    0x5000,
                    KEYEVENTF_EXTENDEDKEY|KEYEVENTF_KEYUP,
                    0);
}

void GetFileName (char *FilePath , char * FileNameExtension)
{
    FILE * fp = fopen ("MusicName.txt" , "w+");
    if (!fp)
        return ;
    _finddata_t Info;
    char cmd[MAX_PATH];
    sprintf (cmd , "%s%s" , FilePath , FileNameExtension);
    long hFind;
    hFind = _findfirst (cmd , &Info);
    fputs (Info.name , fp);
    if (hFind == -1)
    {
        puts ("失败");
        return ;
    }
    while (!_findnext (hFind , &Info))
    {
        fputs ("\n" , fp);
        puts (Info.name);
        fputs (Info.name , fp);
    }
    fputs ("\n" , fp);
    fclose (fp);
    _findclose (hFind);
}

void MciFunction (char *FilePath , char *FileName)
{
   
    char cmd[260];
   
    MCIDEVICEID dev = 0;
    MCI_OPEN_PARMSA open;
    DWORD err;

    MCI_PLAY_PARMS play;
    MCI_BREAK_PARMS br;


    play.dwCallback = NULL;
    play.dwFrom = 0;
    br.nVirtKey = VK_DOWN;
    br.hwndBreak = NULL;
    br.dwCallback = NULL;
     
   
    FileName[strlen (FileName) - 1] = '\0';
    sprintf (cmd , "%s%s" , FilePath , FileName);
    open.lpstrDeviceType = NULL;
    open.lpstrElementName = cmd;
    printf ("%s\n" , cmd);
    err = mciSendCommandA (NULL , MCI_OPEN ,
        MCI_OPEN_ELEMENT | MCI_WAIT | MCI_OPEN_SHAREABLE , (DWORD)(PVOID)&open);
    if (err)
    {
        Error (err);
        return;
    }
    dev = open.wDeviceID;
    int i = 2;
    while (i)
    {
        SetDown ();
        i--;
//        printf ("2\n");
   
    err = mciSendCommand (dev , MCI_BREAK , MCI_BREAK_KEY ,(DWORD)(PVOID)&br);
   
    if (err)
    {
        Error (err);
        return;
    }
    short n = 0;
    n=GetKeyState (br.nVirtKey);//这个函数用来检测按键是否按下抬起
//    printf ("%d\n" , n);
   
    err = mciSendCommand (dev , MCI_PLAY , MCI_WAIT , (DWORD)(PVOID)&play );
   
    }

    if (err)
    {
        Error (err);
        return;
    }
   
    MCI_GENERIC_PARMS close;
    close.dwCallback = NULL;
    mciSendCommand (dev , MCI_CLOSE , 0 , (DWORD)(PVOID)&close);
   
}

int main (void)
{
    char FilePath[MAX_PATH] = "C:\\Users\\yutang\\Desktop\\music\\";
    char FileNameExtension[32] = "*.mp3";
//    gets (FilePath);
//    gets (FileNameExtension);
    char FileName[260];
    FILE *fp = fopen ("MusicName.txt" , "r");
    if (!fp)
        return 0;
    GetFileName (FilePath , FileNameExtension);
    while (fgets (FileName , 260 , fp) != 0)
    {
        MciFunction (FilePath , FileName);
    }
    fclose (fp);
    return 0;
}
终于是弄好了，但是这个keybd_event (); 函数还是有点不太明白