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javascript replace string in js file

Ok so another issue i got
I have a js file that i need to include on my page (i dont have access to edit this js file)
Inside that javascript there is a function wich has a line that i need to edit a variable in there.
lets assume:
Code:
var links = [{"offer_id":"1","title":"Text!","url":"http:\/\/www.site.com\/tracker\/1\/?http:\/\/site.com\/click.php?aff=9917&camp=5626&crt=13346&sid=e6a00014f247fe39de1b_1","footer_text":"text","blank_referrer":"1","active":"1","value":"0.40","creation_time":"1327785202"}];
notice : '&sid=e6a00014f247fe39de1b_1'
i need to add something right after sid=
so that i becomes for example:
Code:
&sid=AlssfIT_e6a00014f247fe39de1b_1
i added: AlssfIT_
any ideas how to achieve this ?
i tried something like
Code:
str.replace("&sid=","&sid="+kwd);
right after i "include" the js file but aparently is not working

I think you're going about it the wrong way. If notice is a variable in the global space you can just replace it normally.
window.someObject.notice = window.someObject.notice.replace("&sid=","&sid="+kwd);
This will of course only work if notice is a variable that is navigable to in the global namespace and is not inside a closure. It is inside a closure if it has a var declaration inside a function() {...}
But, assuming that there is global access to that variable, that will be your easiest way to achieve this.
If not, you can try grabbing the contents of the script and executing it hopefully overwriting the original code. This will only work if your script and the script you are fetching are from the same origin (domain, subdomain, port, protocol, a few other things) - it is impossible otherwise due to the _Same Origin Policy_
Assuming you are at the same origin, you could do something like this (using jquery for simplicity)
( function() {
// First we need the url of the script, we can grab it out of the element directly or it can be hard coded
var scriptLocation = $('script#the-id-of-the-script-element').prop('src');
// Now that we have the location fetch the script again so we can get it as plaintext
// this will usually not do another HTTP request since your browser has it cached
$.get(scriptLocation).done(function(text) { // I prefer the deferred syntax as being more explicit, this is equivalent to $.get(scriptLocation, function(text) {
var newText = text.replace("&sid=","&sid="+kwd);
eval(newText);
});
} )()
Something like this could work.

try regex: (not tested)
myregexp = new RegExp("/&sid=/", "gims");
str.replace(myregexp, "&sid=" + kwd);

How to get the currently loading script name and the url variable of the script?

I am loading a script using the script embed tag and I want to get the url variables and the loading script name inside the script. Is it possible? For Example,
<script src="test.js?id=12"></script>
Inside test.js is there any way to get the url variable id?
Any help would be appreciated.
Thanks,
Karthik

Aside from the answers in the linked post, FWIW with Firefox 4 only you can (with caveats); document.currentScript.src which will return the full url, including arguments.

Thanks for all your efforts I have made that working by assigning an id attribute in the script tag and accessed via jQuery,
<script src="test.js?id=12" id="myScript"></script>
var currentScript = $("#myScript").attr('src'); //This will give me my script src
Thanks,
Karthik

If you want to get a variable from the current URL you can use this:
function queryParser(url){
this.get=function(p){return this.q[p];}
this.q={};
this.map=function(url){
url=url || window.location.search.substring(1);
var url=url.split('&');
var part;
for(var i=0;i<url.length;i++){
part=url[i].split('=');
this.q[part[0]]=part[1];
}
}
this.map(url);
}
var query=new queryParser();
// assuming you have ?test=something
alert(query.get('test'));
I recommend you map the result, so you don't re-parse whenever you want to find a specific element.
I don't really know why you'd pass a query string in a script tag like that, unless you specifically want off-site includes with a simple robust system for various effects. Or are actually using PHP to handle that request.
If you want to "send" a variable to one of your scripts, you can always do:
<script type="text/javascript">
var myVar="I'm in global scope, all scripts can access me";
</script>
<script src="test.js?id=12"></script>
If you really need to get the URL of the currently included script, you can use the code supplied by my peers in the other answers, you can then use:
var query=new queryParser(scriptURL);
alert(query.get('id'));// would alert 12 in your case

Navigating through the link on your comments you can get the proper answer.
Anyway, to make things easier:
var allScripts=document.getElementsByTagName('script');
var indexLastScript= allScripts.length -1;
alert (allScripts[indexLastScript].src);
This will show up "test.js?id=12" as a regular String so its up to you to split it in order to get de param.
Hope it helps, I've tried it on the run over the Chrome Javascript Console. :D.

Is there a way to refresh just the javascript include while doing development?

While doing development on a .js file I'd like to just refresh that file instead of the entire page to save time. Anyone know of any techniques for this?

Here is a function to create a new script element. It appends an incremented integer to make the URL of the script unique (as Kon suggested) in order to force a download.
var index = 0;
function refreshScript (src) {
var scriptElement = document.createElement('script');
scriptElement.type = 'text/javascript';
scriptElement.src = src + '?' + index++;
document.getElementsByTagName('head')[0].appendChild(scriptElement);
}
Then in the Firebug console, you can call it as:
refreshScript('my_script.js');
You'll need to make sure that the index itself is not part of the script being reloaded!
The Firebug Net panel will help you see whether the script is being downloaded. The response status should be "200 OK" and not "304 Not Modified. Also, you should see the index appended in the query string.
The Firebug HTML panel will help you see whether the script element was appended to the head element.
UPDATE:
Here is a version that uses a timestamp instead of an index variable. As #davyM suggests, it is a more flexible approach:
function refreshScript (src) {
var scriptElement = document.createElement('script');
scriptElement.type = 'text/javascript';
scriptElement.src = src + '?' + (new Date).getTime();
document.getElementsByTagName('head')[0].appendChild(scriptElement);
}
Alexei's points are also well-stated.

I suggest you to use Firebug for this purpose.
See this video, it helped me a lot.
http://encosia.com/2009/09/21/updated-see-how-i-used-firebug-to-learn-jquery/

If you're talking about the unfortunate case of client-side/browser caching of your .js file, then you can simply version your .js file. You can:
Rename the .js file itself (not preferred)
Update the include line to reference yourfile.js?1, yourfile.js?2, etc.. Thus forcing the browser to request the latest version from the server. (preferred)

Unfortunately, you have to refresh the web page to see edits to your JavaScript take place. There is no way that I know of to edit JavaScript in "real-time" and see those edits effect without a refresh.
You can use Firebug to insert new JavaScript, and make real-time changes to DOM objects; but you cannot edit JavaScript that has already been run.

If you just fed up refilling the forms while developing just use form recover extensions like this one https://addons.mozilla.org/ru/firefox/addon/lazarus-form-recovery/

showing several JS variables value in chrome extensions

is it possible to get my website 2,3 js variables in an extensions i build so i will be able to see the info behind the site i build
the extension will help me develop my sites

Seeing the variables of a given website (using Content Scripts) is possible. Just inject your own content script, and create an script tag that reads your variables. You cannot use those variables, or modify them on your extension due to some limitations of what Content script can do. You can read the following docs on Communication with the embedding page.
For example the following will read a JS variable in the webpage and transfer its contents to the background page so we can let our extension deal with it. You will notice in the background page inspector, that the variable is successfully passed:
content_script.js
// JS script injection, so that we can read the JS class 'InternalJSVariable'
var postFriendMap = function() {
var textarea = document.getElementById('transfer-dom-area');
textarea.value = JSON.stringify(InternalJSVariable);
};
// Create a dummy textarea DOM.
var textarea = document.createElement('textarea');
textarea.setAttribute('id', 'transfer-dom-area');
textarea.style.display = 'none';
document.body.appendChild(textarea);
// Start injecting the JS script.
var script = document.createElement('script');
script.appendChild(document.createTextNode('(' + postFriendMap + ')();'));
document.body.appendChild(script);
// Inform our world that we have received the friend map data.
chrome.extension.sendRequest({internalVariable: textarea.value});
// Clean up since we no longer need this.
document.body.removeChild(textarea);
background.html
chrome.extension.onRequest.addListener(function(request, sender, sendResponse) {
if (request.internalVariable) {
var internal_object = JSON.parse(request.internalVariable);
console.log(internal_object );
}
});

injecting javascript to FireFox

I'd like to create a handle through which I would be able to inject javascript to Firefox.
I can do it very easily with IE but Firefox is a different story...
Can anyone help?

You can use the grease monkey extension.

What do you want to do exactly:
insert JS in your own browser manually?
insert JS in your browser automatically for some websites?
insert JS in somebody else browser when they visit your website?
Maybe you can describe how you do it with IE. Once we know what you are trying to achieve, we'll probably be able to answer you.

That's how I do it in a manual way, using Firebug extension.
Console.
Find a small triangle on the right that's "Command editor", press it.
Paste the code.
Run
The code:
var b = document.createElement("div");
b.innerHTML = "<button onclick='jarektest();'>text</button>";
document.body.appendChild(b);
// short code typed inline
var s = document.createElement("script");
s.innerHTML = "function jarektest() { alert(document.body.innerHTML); }";
document.body.appendChild(s);
// longer piece, taken from other file
var s2 = document.createElement("script");
s2.src = "file:///J:/lang/js/hello.js";
document.body.appendChild(s2);