type checking in javascript

Question

How can I check if a variable is currently an integer type? I\'ve looked for some sort of resource for this and I think the === operator is important, but I\'m not sure how

Answer 1

I know you're interested in Integer numbers so I won't re answer that but if you ever wanted to check for Floating Point numbers you could do this.

function isFloat( x )
{
    return ( typeof x === "number" && Math.abs( x % 1 ) > 0);
}

Note: This MAY treat numbers ending in .0 (or any logically equivalent number of 0's) as an INTEGER. It actually needs a floating point precision error to occur to detect the floating point values in that case.

Ex.

alert(isFloat(5.2));   //returns true
alert(isFloat(5));     //returns false
alert(isFloat(5.0));   //return could be either true or false