How can I add or update a query string parameter?

Question

With javascript how can I add a query string parameter to the url if not present or if it present, update the current value? I am using jquery for my client side development

Answer 1

I know this is quite old but i want to fires my working version in here.

function addOrUpdateUrlParam(uri, paramKey, paramVal) {
  var re = new RegExp("([?&])" + paramKey + "=[^&#]*", "i");
  if (re.test(uri)) {
    uri = uri.replace(re, '$1' + paramKey + "=" + paramVal);
  } else {
    var separator = /\?/.test(uri) ? "&" : "?";
    uri = uri + separator + paramKey + "=" + paramVal;
  }
  return uri;
}

jQuery(document).ready(function($) {
  $('#paramKey,#paramValue').on('change', function() {
    if ($('#paramKey').val() != "" && $('#paramValue').val() != "") {
      $('#uri').val(addOrUpdateUrlParam($('#uri').val(), $('#paramKey').val(), $('#paramValue').val()));
    }
  });
});

paramKey
  

paramValue
  

NOTE This is a modified version of @elreimundo