Get GET params in JS

getParameterByName.js

// http://stackoverflow.com/a/901144
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 null
  if (!results[2]) return ''
  return decodeURIComponent(results[2].replace(/\+/g, " "))
}