在这里，我介绍利用自己编制的音频解码器来播放音乐的例子，其中，已经将解码器封装到了动态库里，只给出了接口函数及调用规则！

 

动态库头文件为：

 

//打开音频文件   pathname为文件路径名
int __stdcall opensong (char *pathname);

//播放音频文件  position为播放的起始位置
int __stdcall playsong (char *pathname, int position);

//暂停播放
int __stdcall pausesong (char *pathname);

//停止播放，并关闭设备
int __stdcall stopsong (char *pathname);

//播放状态　kind  0:所播放文件的长度　　1：播放状态，为"playing,pause,stoped"等　　2：播放的进度，以毫秒计
int __stdcall statussong (char *pathname, int kind, char *status);

//关于对话框
void about(void);

 

　　应用程序界面为：

 

 

 

程序代码为：

 

#include
#include   
#include
#include "exe.h"
#include "mci.h"

static char pathname[MAX_PATHNAME_LEN];   

static int panelHandle;

int __stdcall WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                       LPSTR lpszCmdLine, int nCmdShow)
{
 if (InitCVIRTE (hInstance, 0, 0) == 0)
  return -1; /* out of memory */
 if ((panelHandle = LoadPanel (0, "exe.uir", PANEL)) < 0)
  return -1;
 DisplayPanel (panelHandle);
 RunUserInterface ();
 DiscardPanel (panelHandle);
 return 0;
}

int CVICALLBACK OkCallback (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 int status;
 char mode[128];
 switch (event)
 {
  case EVENT_COMMIT:
   status = FileSelectPopup ("", "*.mp3", "*.mp3;*.wav;*.mid;*.wma", "打开音频文件", VAL_OK_BUTTON, 0, 0, 1, 1, pathname);
   opensong(pathname);
   playsong(pathname, 0);
   statussong(pathname, 1, mode);
   SetCtrlVal (panelHandle, PANEL_STRING, mode);
   break;
 }
 return 0;
}

int CVICALLBACK QuitCallback (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 switch (event)
 {
  case EVENT_COMMIT:
   QuitUserInterface (0);
   break;
 }
 return 0;
}

int CVICALLBACK stop (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128];
 switch (event)
 {
  case EVENT_COMMIT:
   stopsong(pathname);
   statussong(pathname, 1, status);
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   break;
 }
 return 0;
}

int CVICALLBACK pause (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128]; 
 switch (event)
 {
  case EVENT_COMMIT:
   pausesong(pathname);
   statussong(pathname, 1, status);
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   break;
 }
 return 0;
}

int CVICALLBACK continu (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128];
 int position = 0;
 switch (event)
 {
  case EVENT_COMMIT:
   status[0] = '\0';  
   statussong(pathname, 2, status);
   Fmt(&position, "%i<%s", status);
   playsong(pathname, position);
   
   status[0] = '\0';
   statussong(pathname, 1, status); 
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   break;
 }
 return 0;
}

int CVICALLBACK pre (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128];
 int position;
 switch (event)
 {
  case EVENT_COMMIT:
   statussong(pathname, 1, status);
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   statussong(pathname, 2, status);
   Fmt (&position, "%i<%s", status);
   position += 5000;
   playsong(pathname, position);
   break;
 }
 return 0;
}

int CVICALLBACK back (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128];
 int position;
 switch (event)
 {
  case EVENT_COMMIT:
   statussong(pathname, 1, status);
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   statussong(pathname, 2, status);
   Fmt (&position, "%i<%s", status);
   position -= 5000;
   playsong(pathname, position);
   break;
 }
 return 0;
}

int CVICALLBACK len (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 char status[128];
 switch (event)
 {
  case EVENT_COMMIT:
   statussong(pathname, 0, status);
   SetCtrlVal (panelHandle, PANEL_STRING, status);
   break;
 }
 return 0;
}

int CVICALLBACK aboutme (int panel, int control, int event,
  void *callbackData, int eventData1, int eventData2)
{
 switch (event)
 {
  case EVENT_COMMIT:
   about();
   break;
 }
 return 0;
}