[Javascript] Is integer?

[hassan at webtuitive.com (Hassan Schroeder)]

Peter Lauri wrote:

> Is there any function that checks if something is an integer? I did not find
> one and created this temporary function:
> 
> function isInteger(thenumber) {
> 	thenumberceil = Math.ceil(thenumber);
> 	if(thenumberceil>thenumber) return false;
> 	else return true;	
> }

perhaps more simply: 	return (Math.round(x) == x)? true : false ;

> Why I actually need this is because I need to find out if a year is a "skott
> year" (do not know the English word, but the years when February has 29 days
> instead of 28). Is there any function for that? 

In English, "leap year", but no, I'm not aware of a Date function
to check that.

> function isSkottYear(y) {
> 	yeardiv = y/4;
> 	if(isInteger(yeardiv)) return true;
> 	else return false;
> }

alternatively: 	return ((y % 4) == 0 )? true : false;

Or, using dates directly:

	var D1 = new Date(y, 1, 29);
	var D2 = new Date(y, 2, 1);
	return (D1.getTime() == D2.getTime())? false : true;

There's always more than one way to do it :-)

HTH!
-- 
Hassan Schroeder ----------------------------- hassan@xxxxxxxxxxxxxx
Webtuitive Design ===  (+1) 408-938-0567   === http://webtuitive.com
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