JavaScript Function to get parts of the URL string

function getParameterByName(name, url) { if (!url) url = window.location.href; name = name.replace(/[\[\]]/g, “\\$&”); var regex = new RegExp(“[?&]” + name + “(=([^&#]*)|&|#|$)”), results = regex.exec(url); if (!results) return ”; if (!results[2]) return ”; return decodeURIComponent(results[2].replace(/\+/g, ” “)); }

Balls Collisions Detection