Develop Reference

replace current url without reloading the page

I want to take the current URL from browser and replace the last number param by other number, my example URL:
app#!folder/1/document?p=1
the param to replace - ?p=1 into ?p=3
the param number is generated dynamically so I have to take the param from URL
I want to execute this JavaScript as String,
thanks a lot for any help

I reslove the problem(VAADIN FRAMEWROK) without using javascript
String url = Page.getCurrent().getUriFragment().toString();
url = url.replaceAll("\\?p=([0-9])?", "?p=1");
Page.getCurrent().setUriFragment(url, true);

Unless I'm missing something, just use String#replace() like so
url = url.replace("?p=1", "?p=3");

Note that a modification to the current URL will reload the page unless it happens in the hash part (after the # character), which is obviously what you're trying to do.
The current URL can be modified in javascript via the location.href variable:
location.href = location.href.replace("p=1", "p=3");

Redirect URL paths included with Javascript

I have seen several questions about redirecting to a page via javascript, and that's great, but all of them just redirect to a base url. I want to include a variable path. So say for instance I have http://www.glas.com/my/url/path I want to use window.location.replace() to replace the glas part only, and change it to glass. I'm a beginner at JavaScript so any help would be much appreciated.
This is what I have tried so far:
var path = ''; // this is where I'm stuck
window.location.replace("http://www.glass.com/" + path);
Where the path variable would parse the current URL for anything after the /. I have tried looking at JavaScript's match and regexp, but it all seems very confusing.

Try
window.location = window.location.href.replace('glas', 'glass');

You would do something like:
window.location.href = window.location.href.replace('glas','glass');

Parse URL value and remove anything after the last '/'

My website URL is (example) http://mypage.com/en/?site=main. Then comes JavaScript code that, together with PHP, parses the data.
After that, I need some code that will change the URL inside the adress bar to http://mypage.com/en/, that is, removes the stuff after the last / (slash).
If possible, it is should be jQuery/JavaScript code.

I found something that will work.
You have to use a method called replaceState().
Mozilla developer reference
var str = window.location.href;
window.history.replaceState({}, '', str.substr(0,str.lastIndexOf("/"))+"/");

Use split() function in javascript.
Example :
var url = "http://mypage.com/en/?site=main";
alert(url.split('?')[0]);

window.location.pathname Chrome vs Mozilla

I want to change pathname via function window.location.pathname. I have got this source code.
var hash = window.location.hash;
window.location.pathname = hash;
in Mozilla it works right, but in Chrome doesn't. Chrome write me this adress.
/%23!stranka=novinky&cisloStranky=1&rubrika=novinky&clanek=783?stranka=kontakty#!stranka=novinky&cisloStranky=1&rubrika=novinky&clanek=783
Value of hash is #!stranka=novinky&cisloStranky=1&rubrika=novinky&clanek=783
Have someone any idea?
Thanks.

You'll have to understand that location.hash includes the # itself as well. The rest of the location.hash is, per spec, URLencoded, but the # isn't.
I said "per spec", as Firefox has a bug related to the location.hash property.
If you want to change location.pathname to the hash with the value included, you'll have to encode the # before doing so.
Example:
var hash=location.hash.substring(1)
location.pathname='%23'+hash
If you don't want the hash to be included, just use
var hash=location.hash.substring(1)
location.pathname=hash

jquery/javascript - parsing url to see if you're on a certain page

So say you have some navigation, and you don't/can't use server side code to choose which link is "current". How can you use the first part of the url (as in after the first slash but before any next slash) i.e. (example.com/dashboard/view/16) would return dashboard. Of course there's not always a second slash, it could be (example.com/dashboard). Also before a hash mark i.e. (example.com/dashboard#users) would return dashboard.
Is the best choice to just use location.href and try to write some functions to parse it? Or is there something already made/simpler?

You should be able to do something like this:
var page = window.location.pathname.split('/')[1];
alert(page);​

Could the pathname property of the location be of interest?
From w3schools
hash Returns the anchor portion of a URL
host Returns the hostname and port of a URL
hostname Returns the hostname of a URL
href Returns the entire URL
pathname Returns the path name of a URL
port Returns the port number the server uses for a URL
protocol Returns the protocol of a URL
search Returns the query portion of a URL

It's easy enough to parse it yourself.
window.location.pathname.slice(1).split('/')[0]
is what you are looking for.

$("a[pathname="+location.pathname+"]")
That jQuery collection will contain all of the links that link to the current page. You could narrow it down to certain elements with a more specific selector and then apply a style to it.
For example:
$("#navigation a[pathname="+location.pathname+"]").css('color', 'red');