cmpVersion Is a javascript utility function to compare version strings with multiple decimal points. (such as "1.1.13")

gistfile1.txt

function cmpVersion(a, b) {
    var i, cmp, len, re = /(\.0)+[^\.]*$/;
    a = (a + '').replace(re, '').split('.');
    b = (b + '').replace(re, '').split('.');
    len = Math.min(a.length, b.length);
    for( i = 0; i < len; i++ ) {
        cmp = parseInt(a[i], 10) - parseInt(b[i], 10);
        if( cmp !== 0 ) {
            return cmp;
        }
    }
    return a.length - b.length;
}

function assert(x) {
    if (!x) {
        alert("Assert failed");
        debugger;
    }
}

assert(cmpVersion("1.7.1", "1.7.10") < 0);
assert(cmpVersion("1.7.2", "1.7.10") < 0);
assert(cmpVersion("1.6.1", "1.7.10") < 0);
assert(cmpVersion("1.6.20", "1.7.10") < 0);
assert(cmpVersion("1.7.1", "1.7.10") < 0);

assert(cmpVersion("1.7", "1.7.0") == 0);
assert(cmpVersion("1.7", "1.8.0") < 0);


assert(cmpVersion("1.7.10", "1.7.1") > 0);
assert(cmpVersion("1.7.10", "1.6.1") > 0);
assert(cmpVersion("1.7.10", "1.6.20") > 0);
assert(cmpVersion("1.7.0", "1.7") == 0);
assert(cmpVersion("1.8.0", "1.7") > 0);

assert(cmpVersion("1.7.10", "1.7.10") === 0);
assert(cmpVersion("1.7", "1.7") === 0);
assert(cmpVersion("1.7", "1.7.0") === 0);

assert(isNaN(cmpVersion("1.7", "1..7")));
assert(isNaN(cmpVersion("1.7", "Bad")));
assert(isNaN(cmpVersion("1..7", "1.7")));
assert(isNaN(cmpVersion("Bad", "1.7")));

alert("All done");