delphi 提取网址链接域名

uses System.StrUtils;

//获取主站地址；
function getSite(url:string):string;
var
 dir,s:string;
 p:integer;
begin
 s:=url;
 p:=pos('/',s);
 if(p<=0)then begin result:=url;exit;end;
 dir:=leftstr(s,p-1);
 if(dir='http:')then s:=rightstr(s,length(s)-7);
 if(dir='https:')then s:=rightstr(s,length(s)-8);
 p:=pos('/',s);
 if(p<=0)then begin result:=url;exit;end;
 s:=leftstr(s,p-1);
 result:=s;
end;


procedure TForm1.FormCreate(Sender: TObject);
begin
//用法
text:=getSite('http://www.delphiw.com/show/?id=NjgxNA==');

end;