DELPHI操縱聲卡

檢查聲卡是否安裝
uses mmsystem;
...
function Soundkarte:Boolean;
begin
Result := WaveOutGetNumDevs >0;
end;
檢測聲卡存在
如果你是做一些多媒體播放器之類的程序時，為了完善系統的容錯性，就必須用到一些檢測系統的功能，其中檢測聲卡是否存在就是一個問題，下列程序幫你忙，首先需要在uses部分加入mmsystem ，接著在窗體創建時檢測聲卡：
procedure TForm1.FormCreate(Sender: TObject);
var i:Integer;
begin
i := auxGetNumDevs();
if i<= then
label1.Caption :='系統沒有發現聲卡';
end;
控制聲音音量
當你做一個多媒體播放器時，難免少不了控制音量的大小和左右聲道的播放，下面就介紹一種控制Wave波形輸出設備音量的方法，該方法不是設置主音量。先在窗體上放兩個TTrackBar，分別命名為TrackBar1，TrackBar2，屬性Max都設置為65535，如果覺得刻度太密了，可以把Frequency屬性值設置大一些，然后在Uses段加入MMSystem，并在TrackBar1和TrackBar2的OnChange事件都寫上下列語句：
procedure TForm1.TrackBar1Change(Sender: TObject);
var Wave:string;
begin
Wave:='$'+inttohex(TrackBar1.Position
4)+inttohex(TrackBar2.Position
4);
waveoutsetvolume(0
strtoint(Wave));
end;
獲得和控制音量
unit uMain;
interface
uses
Windows
Messages
SysUtils
Classes
Controls
Forms
Dialogs
ExtCtrls
StdCtrls
mmsystem; //You must add this in the uses line
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Private declarations }
public
myvolume: array[0..10] of longint;
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
procedure TForm1.FormCreate(Sender: TObject);
var
Count
i: integer;
begin
Count := auxGetNumDevs;
for i := 0 to Count do
begin//The i is the device: I.E. 0=Wav Volume
auxgetvolume(i
addr(myvolume[i])); //Gets the values that the user has set
auxsetvolume(i
longint(9000)*65536+longint(9000)); //Sets the volume very very low
end; //The reason for the 9000*65536 + 9000 is if you wanted to do left and right channels
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
var
Count
i: integer;
begin
Count := auxGetNumDevs;
for i := 0 to Count do
begin
auxsetvolume(i
myvolume[i]); //Sets the volume back to the users old settings
end;
end;