function IsNotSelected(f){return (f.options.selectedIndex<0)}
function IsNot1stSelected(f){return (f.options.selectedIndex<1)}
function IsEmpty(s){return (s.length==0)}
function IsNum(n){return /^-?[\d]+\.*[\d]*$/.test(n)}
function IsInt(n){return /^-?[\d]+$/.test(n)}
function IsDate(d,m,y){return (IsInt(d)&&IsInt(m)&&IsInt(y))&&!((d<1||d>31||m<1||m>12)||(d==31&&(m==2||m==4||m==6||m==9||m==11))||(d==30&&m==2)||(d==29&&m==2&&(y%4!=0||(y%100==0&&y%400!=0))))}
function IsEmail(s){return /^[\w\.-]+\@[\w\.-]+\.[\w]+$/.test(s)}
function HasLength(s,m,M){return (s.length>=m&&s.length<=M);}
function Warn(f,m){f.focus();alert(m);return false;}