delphi 实现从下载链接提取文件名的函数

//uses strutils;

 function ExtractUrlFileName(const Url: string): string;
var //www.delphitop.com
str:string;
begin
str:=reversestring(Url);
str:=copy(str,1,pos('/',str)-1);
str:=reversestring(str);
Result:=str;
end;

相反根据链接提取网址 http://www.delphitop.com/html/zifuchuan/1950.html