How do I get the current location of an iframe? - asp.net

I have built a basic data entry application allowing users to browse external content in iframe and enter data quickly from the same page. One of the data variables is the URL.
Ideally I would like to be able to load the iframes current url into a textbox with javascript. I realize now that this is not going to happen due to security issues.
Has anyone done anything on the server side? or know of any .Net browser in browser controls. The ultimate goal is to just give the user an easy method of extracting the url of the page they are viewing in the iframe It doesn't necessarily HAVE to be an iframe, a browser in the browser would be ideal.
Thanks,
Adam

I did some tests in Firefox 3 comparing the value of .src and .documentWindow.location.href in an iframe. (Note: The documentWindow is called contentDocument in Chrome, so instead of .documentWindow.location.href in Chrome it will be .contentDocument.location.href.)
src is always the last URL that was loaded in the iframe without user interaction. I.e., it contains the first value for the URL, or the last value you set up with Javascript from the containing window doing:
document.getElementById("myiframe").src = 'http://www.google.com/';
If the user navigates inside the iframe, you can't anymore access the value of the URL using src. In the previous example, if the user goes away from www.google.com and you do:
alert(document.getElementById("myiframe").src);
You will still get "http://www.google.com".
documentWindow.location.href is only available if the iframe contains a page in the same domain as the containing window, but if it's available it always contains the right value for the URL, even if the user navigates in the iframe.
If you try to access documentWindow.location.href (or anything under documentWindow) and the iframe is in a page that doesn't belong to the domain of the containing window, it will raise an exception:
document.getElementById("myiframe").src = 'http://www.google.com/';
alert(document.getElementById("myiframe").documentWindow.location.href);
Error: Permission denied to get property Location.href
I have not tested any other browser.
Hope it helps!

document.getElementById('iframeID').contentWindow.location.href
You can't access cross-domain iframe location at all.

I use this.
var iframe = parent.document.getElementById("theiframe");
var innerDoc = iframe.contentDocument || iframe.contentWindow.document;
var currentFrame = innerDoc.location.href;

HTA works like a normal windows application.
You write HTML code, and save it as an .hta file.
However, there are, at least, one drawback: The browser can't open an .hta file; it's handled as a normal .exe program. So, if you place a link to an .hta onto your web page, it will open a download dialog, asking of you want to open or save the HTA file. If its not a problem for you, you can click "Open" and it will open a new window (that have no toolbars, so no Back button, neither address bar, neither menubar).
I needed to do something very similar to what you want, but instead of iframes, I used a real frameset.
The main page need to be a .hta file; the other should be a normal .htm page (or .php or whatever).
Here's an example of a HTA page with 2 frames, where the top one have a button and a text field, that contains the second frame URL; the button updates the field:
frameset.hta
<html>
<head>
<title>HTA Example</title>
<HTA:APPLICATION id="frames" border="thin" caption="yes" icon="http://www.google.com/favicon.ico" showintaskbar="yes" singleinstance="no" sysmenu="yes" navigable="yes" contextmenu="no" innerborder="no" scroll="auto" scrollflat="yes" selection="yes" windowstate="normal"></HTA:APPLICATION>
</head>
<frameset rows="60px, *">
<frame src="topo.htm" name="topo" id="topo" application="yes" />
<frame src="http://www.google.com" name="conteudo" id="conteudo" application="yes" />
</frameset>
</html>
There's an HTA:APPLICATION tag that sets some properties to the file; it's good to have, but it isn't a must.
You NEED to place an application="yes" at the frames' tags. It says they belongs to the program too and should have access to all data (if you don't, the frames will still show the error you had before).
topo.htm
<html>
<head>
<title>Topo</title>
<script type="text/javascript">
function copia_url() {
campo.value = parent.conteudo.location;
}
</script>
</head>
<body style="background: lightBlue;" onload="copia_url()">
<input type="button" value="Copiar URL" onclick="copia_url()" />
<input type="text" size="120" id="campo" />
</body>
</html>
You should notice that I didn't used any getElement function to fetch the field; on HTA file, all elements that have an ID becomes instantly an object
I hope this help you, and others that get to this question. It solved my problem, that looks like to be the same as you have.
You can found more information here: http://www.irt.org/articles/js191/index.htm
Enjoy =]

I like your server side idea, even if my proposed implementation of it sounds a little bit ghetto.
You could set the .innerHTML of the iframe to the HTML contents you grab server side. Depending on how you grab this, you will have to pay attention to relative versus absolute paths.
Plus, depending on how the page you are grabbing interacts with other pages, this could totally not work (cookies being set for the page you are grabbing won't work across domains, maybe state is being tracked in Javascript... Lots of reasons this might not work.)
I don't believe that tracking the current state of the page you are trying to mirror is theoretically possible, but I'm not sure. The site could track all sorts of things server side, you won't have access to this state. Imagine the case where on a page load a variable is set to a random value server-side, how would you capture this state?
Do these ideas help with anything?
-Brian J. Stinar-

Does this help?
http://www.quirksmode.org/js/iframe.html
I only tested this in firefox, but if you have something like this:
<iframe name='myframe' id='myframe' src='http://www.google.com'></iframe>
You can get its address by using:
document.getElementById('myframe').src
Not sure if I understood your question correctly but anyways :)

You can use Ra-Ajax and have an iframe wrapped inside e.g. a Window control. Though in general terms I don't encourage people to use iframes (for anything)
Another alternative is to load the HTML on the server and send it directly into the Window as the content of a Label or something. Check out how this Ajax RSS parser is loading the RSS items in the source which can be downloaded here (Open Source - LGPL)
(Disclaimer; I work with Ra-Ajax...)

Ok, so in this application, there is an iframe in which the user is supplied with links or some capacity that allows that iframe to browse to some external site. You are then looking to capture the URL to which the user has browsed.
Something to keep in mind. Since the URL is to an external source, you will be limited in how much you can interact with this iframe via javascript (or an client side access for that matter), this is known as browser cross-domain security, as apparently you have discovered. There are clever work arounds, as presented here Cross-domain, cross-frame Javascript, although I do not think this work around applies in this case.
About all you can access is the location, as you need.
I would suggest making the code presented more resilitant and less error prone. Try browsing the web sometime with IE or FF configured to show javascript errors. You will be surprised just how many javascript errors are thrown, largely because there is a lot of error prone javascript out there, which just continues to proliferate.
This solution assumes that the iframe in question is the same "window" context where you are running the javascript. (Meaning, it is not embedded within another frame or iframe, in which case, the javascript code gets more involved, and you likely need to recursively search through the window hierarchy.)
<iframe name='frmExternal' id='frmExternal' src='http://www.stackoverflow.com'></frame>
<input type='text' id='txtUrl' />
<input type='button' id='btnGetUrl' value='Get URL' onclick='GetIFrameUrl();' />
<script language='javascript' type='text/javascript'>
function GetIFrameUrl()
{
if (!document.getElementById)
{
return;
}
var frm = document.getElementById("frmExternal");
var txt = document.getElementById("txtUrl");
if (frm == null || txt == null)
{
// not great user feedback but slightly better than obnoxious script errors
alert("There was a problem with this page, please refresh.");
return;
}
txt.value = frm.src;
}
</script>
Hope this helps.

You can access the src property of the iframe but that will only give you the initially loaded URL. If the user is navigating around in the iframe via you'll need to use an HTA to solve the security problem.
http://msdn.microsoft.com/en-us/library/ms536474(VS.85).aspx
Check out the link, using an HTA and setting the "application" property of an iframe will allow you to access the document.href property and parse out all of the information you want, including DOM elements and their values if you so choose.

Related

IFRAME src different from the url actually loaded

This is my first question. There is an IFRAME. When I checked the src, it showing some blank.html file. I am unable to read the controls from this. While I am using the F12 option, it was showing some error in a JSP file with the name. Accidently when I right clicked the ie window, this file name was available in the frequently opened files. But this url of the JSP file was not shown anywhere in the code. WHen I tried opening this url while having the original ie session, it is opening and I am able to read the controls.
Is it possible to read the controls on the same frame, without opening in another window. How to read the url opened in the iframe.
Its better if you could also paste your code.
Nevertheless check this.
<iframe id="ifrm" src="demo.html" onload="doSomething()"></iframe>
<script type="text/javascript">
document.getElementById('ifrm').onload = function() {
// put your code here
}
</script>
I have found out the reason. For iframes, we need to use iframe.contentwindow.document instead of just iframe.document.

How can I create a custom StumbleUpon button?

StumbleUpon publishes a Widget script, and documents how to use it to insert a stumbleUpon button (they call it a badge), into a website.
You can generate the markup for a button with their online tool. It looks like this:
<!-- Place this tag where you want the su badge to render -->
<su:badge layout="2" location="http://example.com"></su:badge>
<!-- Place this snippet wherever appropriate -->
<script type="text/javascript">
(function() {
var li = document.createElement('script');
li.type = 'text/javascript';
li.async = true;
li.src = 'https://platform.stumbleupon.com/1/widgets.js';
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(li, s);
})();
</script>
That script element is just a way to delay-load the widgets.js thing. Just from looking at it, I suppose that it works by scanning the document for the <su:badge> elements and replacing them with iframes. The iframes themselves then get their source content from stumbleupon, at a URL like this: http://badge.stumbleupon.com/badge/embed/4/?url=http%3A%2F%2Fexample.com .
The iframe renders visually like this:
The stumbleupon button is the 2nd one. I show the other ones for comparison.
As you can see, the StumbleUpon rendering looks different than all the other guys. SU makes their button look like a "badge" while every other social share widget looks like...uh.... a button.
I'm trying to make the Stumbleupon widget look like a button. I'm pretty sure this is possible. For example, mashable does it (example). Here's what it looks like:
As you can see, the stumbleupon button looks like a button. It's not a badge. Mashable is not using the su:badge thing - they have rendered their own <a> tag, and styled it.
The visual rendering is not a problem; I can figure out how to make a span look like a button, no problem. The problem happens when I click the tag or span. It appears to me that, with the iframe-thing that StumbleUpon uses, it invokes this URL to submit a page for sharing:
http://www.stumbleupon.com/badge/?url=http%3A//example.com/whatever HTTP/1.1
The iframe uses javascript's window.open to request that, and restricts the resizing and so on. This is how it works on mashable. The resulting window looks like this:
This is also what the mashable page does, though it does not use the iframe. The Mashable page contains javascript that just opens the "stumbleupon submit" window directly from within the main mashable page.
But when I try the same thing from my page, the little fixed window gets a 302 redirect from StumbleUpon, and then another 302, which eventually points it to
http://www.stumbleupon.com/submit/visitor
...which does not allow sharing of the link.
This has been a long story, but:
does anyone have any insight as to how I can convince StumbleUpon to let me share a link or URL, from a button that is not contained within an iframe?
What is mashable's secret?
ok here's what I found.
The 302's that eventually pointed me to /submit/visitor happen when both of the following are true:
the user is not logged in
the article has not been stumbled in stumbleupon previously
When that happens, stumbleupon invites you (the user) to login. It won't take you just to the "submit url" page.
If the user is not logged in, but the article HAS been submitted previously, then it takes you to the submit window without a 302. Eventually you will be asked to login, if you proceed with the submission. But the first view of the stumbleupn website in this case gives you a visual indication that you are submitting something.
If the user is logged in, and the article has not been submitted previously, then you get taken right to the submit page.
So I was doing nothing wrong. I just needed to login the first time. This is just an artifact of the user experience offered by StumbleUpon. In my opinion it's sort of strange. It's surprising and therefore wrong. But that's just my opinion.

onbeforeunload dilemma: iframe breaking vs. annoying message on refresh/back buttons click

I'm implementing a search service called SearchInsideOut.
This search service simply replaces web page results by full web pages (Yes, I used iframe).
The problem I have to deal with is iframe-breaking pages.
The promising solution I found is using onbeforeunload to let users decide whether to stay or leave my site.
But this also creates another annoying behavior.
When users click other links in my site, onbeforeunload will also be triggered.
Fortunately, I could solve this case by placing window.onbeforeunload=null in the onclick event of those links of my site.
Unfortunately, I have no idea how to detect external events like clicking "refresh/back" buttons.
What should I do to solve this difficulty?
All suggestions and comments are highly appreciated.
Take as example this site. Try to refresh the page after u typed some text answering to a post. You will see that the page it will ask you to continue ur work or exit. Make another test without answering to a post, just refresh, you will see that the confirm will not showed, because the site is making a test if the "answer" is empty or not.
Example:
<html>
<head>
<script>
function closeIt()
{
var mytext = document.getElementById("mytext").value;
if(mytext != "")
return "Any string value here forces a dialog box to \n" +
"appear before closing the window.";
}
window.onbeforeunload = closeIt;
</script>
</head>
<body>
<textarea id="mytext"></textarea>
</body>
</html>
So it's up to u to decide when the box will show or not. Visit also Microsoft Msdn to understand when and how onbeforeunload works

Alternatives to Iframe

I have been developing a service that allows users to insert information from my database onto their sites by using iframes. The only problem was that the iframe needs to be resizeable and this is one of the biggest problems with iframes as most people already know, aswell as the fact I can access objects on the parent page from within the iframe and vice versa.
I have thought of making an asp.net web servie to server up the HTML and access it by using a get request. However this also has a problem since these request can only be made from the same domain?
What I need to know is the best way to retrieve a small piece of HTML containing customer reviews from server and display it on their page using some sort of AJAX.
Thanks
if your users can add a < script > line to their site pointing to code on your site, you can fairly easily offer a mechanism to build a floating (and resizable) DIV on their page that you jquery.load() with content from your site ...
example:
"To use my service on your site, add the following line to your < head >"
<script type='text/javascript' src='http://mysite.com/scripts/dataget.js />
then add a link or button anywhere and give it a class 'get-date-from-mysite'
< input type='button' value='Click to see the data' class='get-data-from-mysite' />
--
Then in that script you do (something like):
$(function() {
$('.get-data-from-mysite').click(function() {
$('body').append("<div id='mydiv' 'style=position:absolute; z-index:999; left: ...
$('#mydiv').load(' .... // url that sends html for content
});
...etc
resize-able div stuff needs to be added too
I think the jQuery library might be what you need - specifically, look into jQuery Ajax.
Following on what Scott Evernden is explaining, you can add a <script> tag such as:
<script id="my_script_tag" type='text/javascript' src='http://mysite.com/scripts/dataget.js' />
Inside dataget.js you can simply reference the script tag itself by using its "id" (document.getElementById("my_script_tag");) and replace it (insertBefore()) with relevant data.
To get the data from your server you can use JSONP (lots of stuff on SO as well), which is an ajax technique for cross-domain communication.

Asp.net and JavaScript pop up windows

I am writing an intranet application and am considering the use of a pop up window. I am not worried about accessibility since it's an intranet app.
The scenario is such as I need to be able to have the same code be used in a server page as well as in the middle of a process; which is why I decided when using it in the middle of the process, it's best to have it as a pop up window to running out of the real estate on the screen.
Any thoughts on this? I am hesitant to use a pop up window in such a manner as I usually only use it for error messages.
I don't completely understand what you're trying to do, but I think a popup window might be somewhat of an issue if the user's browser automatically blocks popup windows. Plus, if you were trying to run a process in the popup window, the user could close it and no longer have a way to check on the process.
Would it be possible to use Ajax to call back to a web service that gives the page information about the process? You could give the user a way to make the Ajax call to check on the status of the process or just have it continually polling in the background.
Edit:
You said you weren't too familiar with Ajax. For the most part, there are libraries to handle all the of hard details. I'll recommend jQuery because that's what I've been using for a while now.
If you go the Ajax route you'll be able to contain everything on one page and make the updates you need to make when the Ajax call is successful. Depending on how you write the code, it should be pretty reusable if you do it right. It really depends on how specific the your needs on each page.
Take a look at the jQuery documentation though. It may have what you need already built into it. Otherwise, someone else might be able to suggest some reasons why their favorite JavaScript library works better for what you're trying to do.
I think you might want to do something like this:
Inside of the parent page:
<input id="btnShowModal" runat="server" type="button" value='Show Modal' onclick="ShowModal()" />
function ShowModal()
{
var retVal = window.showModalDialog("MyPopup.aspx?param1=value","","center=yes;dialogWidth=200px;dialogHeight=200px;status:0;help:0")
if(retVal != "" && retVal != undefined)
{
//This code will be executed when the modal popup is closed, retVal will contain the value assigned to window.returnValue
}
}
Inside of the modal popup:
<input id="btnSave" runat="server" type="button" value='Save' onclick="Save()" />
function Save()
{
window.returnValue = "Whatever you want returned to the parent here"
window.close()
}
The usual argument against popup windows is that they are unreliable. The user may have disabled script initiated popups, I know I have.
In a controlled environment, such as an inranet, you may be able to be guaranteed that this is not the case, but even so, why risk it, there is an alternative.
Instead of popping up a new window just insert a new, absolutely positioned <div> into the document and insert your content into that using ajax or even an <iframe>. There are lots of examples/libraries on the web.
Thickbox for jQuery for example. There are of course scripts that don't require libraries.
I generally use a div with a z-index and absolute positioning; the .show() can be written and called on demand, it would have a button to .close(), and AJAX can make it seem modal so it must be clicked to close if you so desire. Then again, I hate messageboxes.
I was trying to avoid AJAX, simply because I have never used and don't have the time frame to learn it now. However, I am not totally opposed to it.
In short what I need to do is for the pop up window interact back with the page. Imagine that on the page I am building the links of the chain. Each link has unique properties. When user clicks on "ADD LINK" button, I was thinking have a pop up window with the little form and a Save button. The only issue with this is that a pop up needs to interact with the page; we need to know when something has been saved or not saved.
A div on the same page is one way. A pop up is yet another way. Another catch is that this code (adding new link) needs to be reusable, because I am also going to have a page that just creates new links.

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