parse a(n) URI and return an object with the Key Value pairs. Original Code from the Answer here: http://stackoverflow.com/questions/979975/how-to-get-the-value-from-url-parameter. Check the history for any modifications or compare to the original in the before mentioned Question URL.

querystring.js

//I refactored this to except a parameter, as I would like to parse many URI Queries
function parseQueryString(query) {
  //let's use an object, arrays aren't always the best for Key Value Pairs IMHO
  var query_string = {};
  //original code didn't take in params.
  //use "window.location.search.substring(1)" to get the current URI request.
  
  //this splits each Key Value pair by the "&" seperator
  var vars = query.split("&");
  
  //loop through Key Value Pair strings from the previous split
  for (var i=0;i<vars.length;i++) {
    var pair = vars[i].split("=");
      // If first entry with this name
    if (typeof query_string[pair[0]] === "undefined") {
      query_string[pair[0]] = pair[1];
    	// If second entry with this name
    } else if (typeof query_string[pair[0]] === "string") {
      var arr = [ query_string[pair[0]], pair[1] ];
      query_string[pair[0]] = arr;
    	// If third or later entry with this name
    } else {
      query_string[pair[0]].push(pair[1]);
    }
  } 
    return query_string;
};

refactored to accept a query string parameter (instead of only looking at the current URI/query) and added some light commentary :)