Q146 How can I convert a decimal number into a hexidecimal number?

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The following script will convert any decimal number to a any base upto 36:

<SCRIPT LANGUAGE="JavaScript"><!--
function makeArray() {
    for (i = 0; i<makeArray.arguments.length; i++)
        this[i] = makeArray.arguments[i];
}

var convert = new makeArray('0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z');

function returnBase(number,base) {
    if (number < base) var output = convert[number];
    else {
        var MSD = '' + Math.floor(number / base);
        var LSD = number - MSD*base;
        if (MSD >= base) var output = returnBase(MSD,base) + convert[LSD];
        else var output = convert[MSD] + convert[LSD];
    }
    return output;
}

document.write('Answer = ' + returnBase(510,16));
//--></SCRIPT>

Martin Honnen kindly pointed out the following solution:

<SCRIPT LANGUAGE="JavaScript"><!--
var n = 16;
alert(n.toString(16));
//--></SCRIPT>

However, as Jukka Korpela points out:

it seems to me that at least on Internet Explorer 3.0 and Opera 3.60, the parameter (16) is ignored - and this means getting the wrong result without any warning. Since the toString solution is probably commonly suggested, perhaps it's useful to mention but with a warning that it does not work on all browsers, so it's better to use another solution.