Javascript Random Number?

Question

I have the following script;

Timer=0;
function countdown(auctionid)
{
var auctions;
var divs;

Timer=Timer+1;

if((Timer%10=="0")||(Timer=="1")){
$.get("current.php", {
id:auctionid},
function(data){
auctions=data.split("||");
for(n=0;n<=auctions.length;n++)
{
if(auctions[n] != undefined)
{
divis=auctions[n].split("##");

$('#futu'+divis[0]).html(divis[1]);
}}
});
}
var cauctionid="auctionid";
var tauctions=auctionid.split("|");
for(i=0;i<=tauctions.length;i++)
{
if(tauctions[i] != undefined)
{
var dd=$('#futu'+tauctions[i]).text();
var cdd=dd-1;
$('#futu'+tauctions[i]).html(cdd);

dd=dd*1000;
dday=Math.floor(dd/(60*60*1000*24)*1)
dhour=Math.floor(dd/(60*60*1000)*1)
dmin=Math.floor((dd%(60*60*1000))/(60*1000)*1)
dsec=Math.floor(((dd%(60*60*1000))%(60*1000))/1000*1)

if(dday==0&&dhour==0&&dmin==0&&dsec==0){
$('#Bid'+tauctions[i]).html("SOLD");
//return
}
if(dhour <=9)
{
dhour = "0"+dhour;
}
if(dmin <=9)
{
dmin = "0"+dmin;
}
if(dsec <=9)
{
dsec = "0"+dsec;
}

if(dd>=1000)
{
var valll=dhour+":"+dmin+":"+dsec;
}

if(dd<1000)
{
var valll="00:00:00";
}

$('#Bid'+tauctions[i]).html(valll);
}}
refreshID=setTimeout("countdown('"+auctionid+"')",1000);
}

On the line that reads;

if((Timer%10=="0")||(Timer=="1")){

How do i make the 10, a random number between 2 and 12?

Answer 1

You want to use the random() function. There is no version that returns an integer unfortunately, only a float between 0 and 1, so you'll need to do a few operations. Try the following:

var randomNum = Math.floor(Math.random() * 10) + 2;

This should generate a random integral number between 2 (inclusive) and 12 (exclusive). Change 10 to 11 if you want the 12 to be inclusive, of course.

Answer 2

if((Timer%10=="0")||(Timer=="1")) {

would be better as

if((Timer%10===0)||(Timer===1)){

There's no reason here to force a constant string to number conversion.

Answer 3

See the answers to this question which also allows you to set the seed value.