请问各大侠,如何在DELPHI中控制主音量???

Question

怎样在DELPHI中控制系统的主音量,和设置静音,我看到很多帖子都是用Waveoutsetvolume(deviceid,vol)函数,对于播放一般的文件,
勉强是可以了,但是对播放CD时音量控制就无效了,怎么办?

Answer 1

怎样在DELPHI中控制系统的主音量,和设置静音,我看到很多帖子都是用Waveoutsetvolume(deviceid,vol)函数,对于播放一般的文件,
勉强是可以了,但是对播放CD时音量控制就无效了,怎么办?

Answer 2

unit Volume; interface uses windows,mmsystem; type
    Tvolume=record
       left,right:word; // 取值范围 0--65535
    end; procedure fillstruct(control:PMixerControl;var Cdetails:tMIXERCONTROLDETAILS); 
function getpeak(control:PMixerControl;var peak:integer):boolean; 
function setvolume(control:Pmixercontrol; volume:Tvolume):boolean; 
function getvolume(control:Pmixercontrol; volume:Tvolume):boolean; var
    mcontrols:array of array of array of PMixerControl; //mixer的数组,单声卡可以不用
    fmixerhandle:HMIXER; //mixer的句柄 implementation procedure fillstruct(control:PMixerControl;var Cdetails:tMIXERCONTROLDETAILS); 
begin
    Cdetails.cbStruct:=sizeof(cdetails);
    cdetails.dwControlID:=Control.dwControlID;
    cdetails.cbDetails:=sizeof(integer);
    cdetails.hwndOwner:=0; 
end; function getpeak(control:PMixerControl;var peak:integer):boolean; 
var
   details:TMixerControlDetailsSigned;
   cdetails:tMIXERCONTROLDETAILS; 
begin
    Result:=false;
    if control.dwControlType<> mixercontrol_controltype_peakmeter then exit;
    cdetails.cChannels:=1;
    cdetails.paDetails:=@details;
    fillstruct(control,cdetails);
    result:=mixerGetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0; 
end; function setvolume(control:Pmixercontrol; volume:Tvolume):boolean; 
var
    details:array[0..30] of integer;
    cdetails:tMIXERCONTROLDETAILS; 
begin
    fillstruct(control,cdetails);
    cdetails.cChannels:=2;
    cdetails.paDetails:=@details;
    details[0]:=volume.left;
    details[1]:=volume.right;
    result:=mixerSetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0;
    volume.left:=details[0];
    volume.right:=details[1]; 
end; function getvolume(control:Pmixercontrol; volume:Tvolume):boolean; 
var
    details:array[0..30] of integer;
    cdetails:tMIXERCONTROLDETAILS; 
begin
    fillstruct(control,cdetails);
    cdetails.cChannels:=2;
    cdetails.paDetails:=@details;
    result:=mixerGetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0;
    volume.left:=details[0];
    volume.right:=details[1]; 
end; end. // 调用方法: 
procedure TForm1.Button1Click(Sender: TObject); 
var s : Tvolume;
     kz : Pmixercontrol; 
begin
    new(kz); //<------------ 此处一定要分配内存 
kz.dwControlID := 0; 
s.left := 0; 
s.right := 0; 
try 
setvolume(kz,s); 
except 
end; 
freemem(kz); 
end;