How to use jquery to manipulate the querystring

Question

I have a select dropdown with id\'s mapped to values. On the onChange event I want to redirect to the same url but with \'id=value\' appended to the querystring.

How do

Answer 1

Based on CoffeeMonster's answer:

There is a problem when the location.href contains a hash part:

www.example.com#hash becomes www.example.com#hash?id=whatever which results in ?id=whatever not being interpreted by the server.

Fixed it by removing the hash part of the url: url.split("#")[0];

// put function into jQuery namespace
jQuery.redirect = function(url, params) {

    url = url || window.location.href || '';
    url = url.split("#")[0];
    url =  url.match(/\?/) ? url : url + '?';

    for ( var key in params ) {
        var re = RegExp( ';?' + key + '=?[^&;]*', 'g' );
        url = url.replace( re, '');
        url += ';' + key + '=' + params[key]; 
    }  
    // cleanup url 
    url = url.replace(/[;&]$/, '');
    url = url.replace(/\?[;&]/, '?'); 
    url = url.replace(/[;&]{2}/g, ';');
    // $(location).attr('href', url);
    window.location.replace( url ); 
};

Now www.example.com#hash becomes www.example.com?id=whatever