Replacing query string parameter values.

index.js

// Update the appropriate href query string parameter
function paramReplace(name, string, value) {
  // Find the param with regex
  // Grab the first character in the returned string (should be ? or &)
  // Replace our href string with our new value, passing on the name and delimeter
  var re = new RegExp("[\\?&]" + name + "=([^&#]*)"),
      delimeter = re.exec(string)[0].charAt(0),
      newString = string.replace(re, delimeter + name + "=" + value);

  return newString;
}

To replace all the query parameters with given value you can use something like this:

url.replace(/([?&])(((?![?&#=]).)*=)((?![?&#=]).)*/g, '$1$2xxx');