用多媒体库 Bass.dll 播放 mp3 [6] - 是否循环播放

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;

type
TForm1 = class(TForm)
OpenDialog1: TOpenDialog;
Button1: TButton;
Button2: TButton;
Button3: TButton;
CheckBox1: TCheckBox;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure CheckBox1Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

uses Bass;

var
hs: HSTREAM;  {流句柄}

procedure TForm1.FormCreate(Sender: TObject);
begin
CheckBox1.Caption := '循环播放';

if HiWord(BASS_GetVersion) <> BASSVERSION then
MessageBox(0, '"Bass.dll" 文件版本不合适! ', nil, MB_ICONERROR);

if not BASS_Init(-1, 44100, 0, 0, nil) then
ShowMessage('初始化错误');
end;

{打开}
procedure TForm1.Button1Click(Sender: TObject);
var
Mp3Path: AnsiString;
begin
BASS_StreamFree(hs);

OpenDialog1.Filter := 'Mp3 文件(*.mp3)|*.mp3|Wav 文件(*.wav)|*wav';
if OpenDialog1.Execute then
Mp3Path := AnsiString(OpenDialog1.FileName);

hs := BASS_StreamCreateFile(False, PAnsiChar(Mp3Path), 0, 0, 0);
{像下面这样建立播放流, 直接就是循环播放的}
//hs := BASS_StreamCreateFile(False, PAnsiChar(Mp3Path), 0, 0, BASS_SAMPLE_LOOP);

if hs < BASS_ERROR_ENDED then
Text := '打开失败'
else
Text := string(Mp3Path);
end;

{播放}
procedure TForm1.Button2Click(Sender: TObject);
begin
BASS_ChannelPlay(hs, False);
end;

{暂停}
procedure TForm1.Button3Click(Sender: TObject);
begin
BASS_ChannelPause(hs);
end;

{是否循环播放}
procedure TForm1.CheckBox1Click(Sender: TObject);
begin
if CheckBox1.Checked then
BASS_ChannelFlags(hs, BASS_SAMPLE_LOOP, BASS_SAMPLE_LOOP)
else
BASS_ChannelFlags(hs, 0, BASS_SAMPLE_LOOP);
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
BASS_Free;
end;

end.

object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 90
ClientWidth = 207
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
OnCreate = FormCreate
OnDestroy = FormDestroy
PixelsPerInch = 96
TextHeight = 13
object Button1: TButton
Left = 25
Top = 17
Width = 75
Height = 25
Caption = #25171#24320
TabOrder = 0
OnClick = Button1Click
end
object Button2: TButton
Left = 25
Top = 48
Width = 75
Height = 25
Caption = #25773#25918
TabOrder = 1
OnClick = Button2Click
end
object Button3: TButton
Left = 106
Top = 17
Width = 75
Height = 25
Caption = #26242#20572
TabOrder = 2
OnClick = Button3Click
end
object CheckBox1: TCheckBox
Left = 110
Top = 52
Width = 97
Height = 17
Caption = 'CheckBox1'
TabOrder = 3
OnClick = CheckBox1Click
end
object OpenDialog1: TOpenDialog
Left = 192
Top = 8
end
end