uses ShellAPI

function ExecAndWait(const ExecuteFile, ParamString : string):
boolean;
var
SEInfo: TShellExecuteInfo;
ExitCode: DWORD;
begin
FillChar(SEInfo, SizeOf(SEInfo), 0);
SEInfo.cbSize := SizeOf(TShellExecuteInfo);
with SEInfo do begin
fMask := SEE_MASK_NOCLOSEPROCESS;
Wnd := Application.Handle;
lpFile := PChar(ExecuteFile);
lpParameters := PChar(ParamString);
nShow := SW_HIDE;
end;
if ShellExecuteEx(@SEInfo) then
begin
repeat
Application.ProcessMessages;
GetExitCodeProcess(SEInfo.hProcess, ExitCode);
until (ExitCode <> STILL_ACTIVE) or Application.Terminated;
Result:=True;
end
else Result:=False;
end;

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利用以上函数：

procedure TForm1.Button1Click(Sender: TObject);
begin
ExecAndWait('regsvr32','/s' + 'F:\test\test.dll');
end;