function TForm1.GetsysShortDateFormat: string;
var
sgs:string;
begin
setlength(sgs,12);
GetLocaleInfo(LOCALE_SYSTEM_DEFAULT,LOCALE_SSHORTDATE ,PChar(sgs),12);
result:=string(pchar(sgs));
end;

function TForm1.GetsysLongDateFormat: string;
var
sgs:string;
begin
setlength(sgs,12); //delphitop.com
GetLocaleInfo(LOCALE_SYSTEM_DEFAULT,LOCALE_SLONGDATE ,PChar(sgs),12);
result:=string(pchar(sgs));
end;

function TForm1.GetsysTimeFormat: string;
var
sgs:string;
begin
setlength(sgs,12);
GetLocaleInfo(LOCALE_SYSTEM_DEFAULT,LOCALE_STIMEFORMAT ,PChar(sgs),12);
result:=string(pchar(sgs));
end;

var
str: string;
begin
str := 'HH:mm:ss';
if SetLocaleInfoa(LOCALE_SYSTEM_DEFAULT, LOCALE_STIMEFORMAT, PChar(str)) then
begin
showmessage('时间格式设置成功');
end;

var
str: string;
begin
str := 'yyyy-MM-dd';
if SetLocaleInfoa(LOCALE_SYSTEM_DEFAULT, LOCALE_SSHORTDATE, PChar(str)) then
begin
showmessage('短日期格式设置成功');
end;

var
str: string;
begin
str := 'yyyy-MM-dd';
if SetLocaleInfoa(LOCALE_SYSTEM_DEFAULT, LOCALE_SLONGDATE, PChar(str)) then
begin
showmessage('长日期格式设置成功');
end;