用多媒体库 Bass.dll 播放 mp3 [17] : 如何从内存流播放 - 回复 "小李子子" 的问题

问题来源: http://www.cnblogs.com/del/archive/2008/12/20/1022124.html#1408043

这是从 http://www.cnblogs.com/del/archive/2008/08/17/1269958.html 修改来的.

---

代码文件:

---

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    OpenDialog1: TOpenDialog;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses Bass;

var
  hs: HSTREAM;
  mem: TMemoryStream; {新加的}

procedure TForm1.FormCreate(Sender: TObject);
begin
  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;

procedure TForm1.Button1Click(Sender: TObject);
var
  Mp3Path: string;
begin
  OpenDialog1.Filter := 'Mp3 文件(*.mp3)|*.mp3|Wav 文件(*.wav)|*wav';
  if OpenDialog1.Execute then Mp3Path := OpenDialog1.FileName;

  {下面几行是与原来不同的代码}
  if not Assigned(mem) then mem := TMemoryStream.Create;
  mem.LoadFromFile(Mp3Path);
  mem.Position := 0;

  BASS_StreamFree(hs);
  hs := BASS_StreamCreateFile(True, mem.Memory, 0, mem.Size, 0);

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

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

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

procedure TForm1.Button4Click(Sender: TObject);
begin
  BASS_ChannelStop(hs);
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  BASS_Free;
  if Assigned(mem) then mem.Free; {这也是新加的}
end;

end.

窗体文件:

---

object Form1: TForm1
  Left = 0
  Top = 0
  Caption = 'Form1'
  ClientHeight = 117
  ClientWidth = 202
  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 = 16
    Top = 17
    Width = 75
    Height = 25
    Caption = #25171#24320
    TabOrder = 0
    OnClick = Button1Click
  end
  object Button2: TButton
    Left = 112
    Top = 17
    Width = 75
    Height = 25
    Caption = #25773#25918
    TabOrder = 1
    OnClick = Button2Click
  end
  object Button3: TButton
    Left = 112
    Top = 48
    Width = 75
    Height = 25
    Caption = #26242#20572
    TabOrder = 2
    OnClick = Button3Click
  end
  object Button4: TButton
    Left = 112
    Top = 79
    Width = 75
    Height = 25
    Caption = #20572#27490
    TabOrder = 3
    OnClick = Button4Click
  end
  object OpenDialog1: TOpenDialog
    Left = 40
    Top = 56
  end
end