sid:=createhttpsession();
 sethttpcallback(sid,findfunction("DownProg")); //进度回调
 s:="http://www.baidu.com"; //小型下载
 GetHttp(s,60000,v,code);
 echo "\r\n---->done",'->',code,'->',length(v);
 return 1;

//进度回调函数
function DownProg(sid,AlldnB,dnB,AllupB,upB); //progresscallback
begin
 if dnB > 0 then //如果已开始下载则保存到本地
 begin
   if dnB>sysparams["__DownProg_dnB"] then begin
    hc:=GetHttpContent(sid);//获取当前内容
    ret:=WriteFile(rwRaw(),'',"E:\\test\\log_Data.txt",0,Length(hc),hc);
   end;
   sysparams["__DownProg_dnB"]:=dnB;
   echo "->",dnB$"/",AlldnB,"\r\n";
 end;
 return 0; //not done
end;