url « alert « jQuery Q&A

1. How to alert when url contains[...]    stackoverflow.com

How can I disable an input-field with jQuery using GM if the url contains text? I tried

$(document).ready( function() {
    if($("url:contains('text')")){
        $(".input[id=field-owner]:disabled");
  ...

2. If was not alert go to url else do not go    stackoverflow.com

I want make validation jquery without using from plugin, problem is here that after click on button and get alert(if field is empty) it go to url # that there is ...

3. $.getJSON(url, function(data) { alert(data['Article']['title']); });    forum.jquery.com