Usage - Example URL: http://www.example.com/index.php?id=1&image=awesome.jpg Calling getQueryVariable("id") - would return "1". Calling getQueryVariable("image") - would return "awesome.jpg".

getURLVariable.js

function getQueryVariable(variable) {
  var query = window.location.search.substring(1);
  var vars = query.split("&");
  for (var i=0;i<vars.length;i++) {
    var pair = vars[i].split("=");
    if(pair[0] == variable){
      return pair[1];
    }
  }
  return(false);
}