一个VC++ MFC播放器代码文件

// MFC音乐播放器Dlg.cpp : implementation file
#include "stdafx.h"
#include "MFC音乐播放器.h"
#include "MFC音乐播放器Dlg.h"
#include "Mmsystem.h"
#include "Digitalv.h"
#pragma comment(lib,"Winmm.lib")
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
//定义三个全局变量
HWND m_hWnd;
DWORD DeviceID;
MCI_OPEN_PARMS mciopenparms;
void Load(HWND hWnd,CString strFilepath)
{
	m_hWnd=hWnd;
	mciSendCommand(DeviceID,MCI_CLOSE,0,0);//在加载文件前先清空上一次播放的设备
	mciopenparms.lpstrElementName=strFilepath;//将音乐文件路径传给设备
	DWORD dwReturn;
	if(dwReturn=mciSendCommand(NULL,MCI_OPEN,MCI_OPEN_ELEMENT|MCI_WAIT,(DWORD)(LPVOID)&mciopenparms))
	{
		//如果打开文件失败，则将出错信息储存在buffer，并显示出错警告
		char buffer[256];
		mciGetErrorString(dwReturn,buffer,256);
		MessageBox(hWnd,buffer,"出错警告!",MB_ICONHAND|MB_ICONERROR|MB_ICONSTOP);
	}
	DeviceID=mciopenparms.wDeviceID;
	//打开文件成功就关联文件到设备
}
void play()
{
	MCI_PLAY_PARMS mciplayparms;
	mciplayparms.dwCallback=(DWORD)m_hWnd;
	mciplayparms.dwFrom=0;//每次播放都是从0开始播放
	mciSendCommand(DeviceID,MCI_PLAY,MCI_FROM|MCI_NOTIFY,(DWORD)(LPVOID)&mciplayparms);
}
void pause()
{
	mciSendCommand(DeviceID,MCI_PAUSE,0,0);
}
void resume()
{
	mciSendCommand(DeviceID,MCI_RESUME,0,0);
}
void stop()
{
	mciSendCommand(DeviceID,MCI_STOP,0,0);
	mciSendCommand(DeviceID,MCI_CLOSE,0,0);
	//当点击停止按钮时，将所有的信息都清除掉
}
DWORD setvolume(DWORD vol)
{
	MCI_DGV_SETAUDIO_PARMS setvolume;//这是设置音量的参数数据结构
	setvolume.dwCallback=NULL;
	setvolume.dwItem=MCI_DGV_SETAUDIO_VOLUME;//动作是设置音量
	setvolume.dwValue=vol;//音量值是vol
	mciSendCommand(DeviceID,MCI_SETAUDIO,MCI_DGV_SETAUDIO_ITEM|MCI_DGV_SETAUDIO_VALUE,(DWORD)(LPVOID)&setvolume);
	return 0;
}
/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About
class CAboutDlg : public CDialog
{
public:
	CAboutDlg();
// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA
	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL
// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};
CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
	//{{AFX_DATA_INIT(CAboutDlg)
	//}}AFX_DATA_INIT
}
void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CAboutDlg)
	//}}AFX_DATA_MAP
}
BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CMFCDlg dialog
CMFCDlg::CMFCDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CMFCDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CMFCDlg)
	m_int = 0;
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDI_ICON1);
}
void CMFCDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CMFCDlg)
	DDX_Control(pDX, IDC_SLIDER, m_slider);
	DDX_Text(pDX, IDC_vol, m_int);
	//}}AFX_DATA_MAP
}
BEGIN_MESSAGE_MAP(CMFCDlg, CDialog)
	//{{AFX_MSG_MAP(CMFCDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_about, Onabout)
	ON_BN_CLICKED(IDC_exitbt, Onexitbt)
	ON_NOTIFY(NM_CUSTOMDRAW, IDC_SLIDER, OnCustomdrawSlider)
	ON_BN_CLICKED(IDC_filechoice, Onfilechoice)
	ON_BN_CLICKED(IDC_play, Onplay)
	ON_BN_CLICKED(IDC_pause, Onpause)
	ON_BN_CLICKED(IDC_stop, Onstop)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CMFCDlg message handlers
BOOL CMFCDlg::OnInitDialog()
{
	CDialog::OnInitDialog();
	// Add "About..." menu item to system menu.
	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);
	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}
	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	m_slider.SetRange(0,1000);//滑块的移动范围0~1000
	m_slider.SetPos(500);//滑块指针的初始位置设为500代表初始音量为50
	GetDlgItem(IDC_play)->EnableWindow(false);//文件没有读取时所有按钮应该是不可选的
	GetDlgItem(IDC_pause)->EnableWindow(false);
	GetDlgItem(IDC_stop)->EnableWindow(false);
	// TODO: Add extra initialization here
	
	return TRUE;  // return TRUE  unless you set the focus to a control
}
void CMFCDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}
// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.
void CMFCDlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting
		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);
		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;
		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}
// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CMFCDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}
void CMFCDlg::Onabout() 
{
CAboutDlg dlg;
dlg.DoModal();	
}
void CMFCDlg::Onexitbt() 
{
	CDialog::OnCancel();	
}
void CMFCDlg::OnCustomdrawSlider(NMHDR* pNMHDR, LRESULT* pResult) 
{
    UpdateData(true);
	m_int=m_slider.GetPos()/10;
	setvolume(m_slider.GetPos());
	UpdateData(false);
	*pResult = 0;
}
void CMFCDlg::Onfilechoice() 
{
	char szFileFilter[]="mp3文件(*.mp3)|*.mp3|"
                        "wma文件(*.wma)|*.wma|"
						"wav文件(*.wav)|*.wav|"
						"所有文件(*.*)|*.*|";
	CFileDialog dlg(true,NULL,NULL,OFN_HIDEREADONLY,szFileFilter);
	if(dlg.DoModal()==IDOK)
	{
		CString strFilepath=dlg.GetPathName();
		CString strFilename=dlg.GetFileName();
		SetDlgItemText(IDC_filename,strFilename);
		Load(this->m_hWnd,strFilepath);
		GetDlgItem(IDC_play)->EnableWindow(true);//文件读取成功时所有按钮变可选的
	    GetDlgItem(IDC_pause)->EnableWindow(true);
	    GetDlgItem(IDC_stop)->EnableWindow(true);
	}
}
void CMFCDlg::Onplay() 
{
play();
SetDlgItemText(IDC_pause,"暂停");	
}
void CMFCDlg::Onpause() 
{
CString strtemp;
GetDlgItemText(IDC_pause,strtemp);//获取按钮状态
if(strtemp.Compare("暂停")==0)
{
	pause();
	SetDlgItemText(IDC_pause,"恢复");
}	
if(strtemp.Compare("恢复")==0)
{
	resume();
	SetDlgItemText(IDC_pause,"暂停");
}	
}
void CMFCDlg::Onstop() 
{
stop();	
SetDlgItemText(IDC_pause,"暂停");
GetDlgItem(IDC_play)->EnableWindow(false);//当stop按钮按下时,播放和暂停应该均不可用
GetDlgItem(IDC_pause)->EnableWindow(false);
}