[html] Best Way to View Generated Source of Webpage?

I'm looking for a tool that will give me the proper generated source including DOM changes made by AJAX requests for input into W3's validator. I've tried the following methods:

1. Web Developer Toolbar - Generates invalid source according to the doc-type (e.g. it removes the self closing portion of tags). Loses the doctype portion of the page.
2. Firebug - Fixes potential flaws in the source (e.g. unclosed tags). Also loses doctype portion of tags and injects the console which itself is invalid HTML.
3. IE Developer Toolbar - Generates invalid source according to the doc-type (e.g. it makes all tags uppercase, against XHTML spec).
4. Highlight + View Selection Source - Frequently difficult to get the entire page, also excludes doc-type.

Is there any program or add-on out there that will give me the exact current version of the source, without fixing or changing it in some way? So far, Firebug seems the best, but I worry it may fix some of my mistakes.

Solution

It turns out there is no exact solution to what I wanted as Justin explained. The best solution seems to be to validate the source inside of Firebug's console, even though it will contain some errors caused by Firebug. I'd also like to thank Forgotten Semicolon for explaining why "View Generated Source" doesn't match the actual source. If I could mark 2 best answers, I would.

Justin is dead on. The key point here is that HTML is just a language for describing a document. Once the browser reads it, it's gone. Open tags, close tags, and formatting are all taken care of by the parser and then go away. Any tool that shows you HTML is generating it based on the contents of the document, so it will always be valid.

I had to explain this to another web developer once, and it took a little while for him to accept it.

You can try it for yourself in any JavaScript console:

el = document.createElement('div');
el.innerHTML = "<p>Some text<P>More text";
el.innerHTML; // <p>Some text</p><p>More text</p>

The un-closed tags and uppercase tag names are gone, because that HTML was parsed and discarded after the second line.

The right way to modify the document from JavaScript is with document methods (createElement, appendChild, setAttribute, etc.) and you'll observe that there's no reference to tags or HTML syntax in any of those functions. If you're using document.write, innerHTML, or other HTML-speaking calls to modify your pages, the only way to validate it is to catch what you're putting into them and validate that HTML separately.

That said, the simplest way to get at the HTML representation of the document is this:

document.documentElement.innerHTML

Check out "View Rendered Source" chrome extension:

https://chrome.google.com/webstore/detail/view-rendered-source/ejgngohbdedoabanmclafpkoogegdpob/

Using the Firefox Web Developer Toolbar (https://addons.mozilla.org/en-US/firefox/addon/60)

Just go to View Source -> View Generated Source

I use it all the time for the exact same thing.

If you load the document in Chrome, the Developer|Elements view will show you the HTML as fiddled by your JS code. It's not directly HTML text and you have to open (unfold) any elements of interest, but you effectively get to inspect the generated HTML.

In the elements tab, right click the html node > copy > copy element - then paste into an editor.

As has been mentioned above, once the source has been converted into a DOM tree, the original source no longer exists in the browser. Any changes you make will be to the DOM, not the source.

However, you can parse the modified DOM back into HTML, letting you see the "generated source".

1. In Chrome, open the developer tools and click the elements tab.
2. Right click the HTML element.
3. Choose copy > copy element.
4. Paste into an editor.

You can now see the current DOM as an HTML page.

This is not the full DOM

Note that the DOM cannot be fully represented by an HTML document. This is because the DOM has many more properties than the HTML has attributes. However this will do a reasonable job.

I think IE dev tools (F12) has; View > Source > DOM (Page)

You would need to copy and paste the DOM and save it to send to the validator.

I was able to solve a similar issue by logging the results of the ajax call to the console. This was the html returned and I could easily see any issues that it had.

in my .done() function of my ajax call I added console.log(results) so I could see the html in the debugger console.

function GetReversals() {_x000D_
    $("#getReversalsLoadingButton").removeClass("d-none");_x000D_
    $("#getReversalsButton").addClass("d-none");_x000D_
_x000D_
    $.ajax({_x000D_
        url: '/Home/LookupReversals',_x000D_
        data: $("#LookupReversals").serialize(),_x000D_
        type: 'Post',_x000D_
        cache: false_x000D_
    }).done(function (result) {_x000D_
        $('#reversalResults').html(result);_x000D_
        console.log(result);_x000D_
    }).fail(function (jqXHR, textStatus, errorThrown) {_x000D_
        //alert("There was a problem getting results.  Please try again. " + jqXHR.responseText + " | " + jqXHR.statusText);_x000D_
        $("#reversalResults").html("<div class='text-danger'>" + jqXHR.responseText + "</div>");_x000D_
    }).always(function () {_x000D_
        $("#getReversalsLoadingButton").addClass("d-none");_x000D_
        $("#getReversalsButton").removeClass("d-none");_x000D_
    });_x000D_
}

In Firefox, just ctrl-a (select everything on the screen) then right click "View Selection Source". This captures any changes made by JavaScript to the DOM.

Why not type this is the urlbar?

javascript:alert(document.body.innerHTML)

I know this is an old post, but I just found this piece of gold. This is old (2006), but still works with IE9. I personnally added a bookmark with this.

Just copy paste this in your browser's address bar:

javascript:void(window.open("javascript:document.open(\"text/plain\");document.write(opener.document.body.parentNode.outerHTML)"))

As for firefox, web developper tool bar does the job. I usually use this, but sometimes, some dirty 3rd party asp.net controls generates differents markups based on the user agent...

EDIT

As Bryan pointed in the comment, some browser remove the javascript: part when copy/pasting in url bar. I just tested and that's the case with IE10.

Only thing i found is the BetterSource extension for Safari this will show you the manipulated source of the document only downside is nothing remotely like it for Firefox

This is an old question, and here's an old answer that has once worked flawlessly for me for many years, but doesn't any more, at least not as of January 2016:

The "Generated Source" bookmarklet from SquareFree does exactly what you want -- and, unlike the otherwise fine "old gold" from @Johnny5, displays as source code (rather than being rendered normally by the browser, at least in the case of Google Chrome on Mac):

https://www.squarefree.com/bookmarklets/webdevel.html#generated_source

Unfortunately, it behaves just like the "old gold" from @Johnny5: it does not show up as source code any more. Sorry.

alert(document.documentElement.outerHTML);

I had the same problem, and I've found here a solution:

http://ubuntuincident.wordpress.com/2011/04/15/scraping-ajax-web-pages/

So, to use Crowbar, the tool from here:

http://simile.mit.edu/wiki/Crowbar (now (2015-12) 404s)
wayback machine link:
http://web.archive.org/web/20140421160451/http://simile.mit.edu/wiki/Crowbar

It gave me the faulty, invalid HTML.

In the Web Developer Toolbar, have you tried the Tools -> Validate HTML or Tools -> Validate Local HTML options?

The Validate HTML option sends the url to the validator, which works well with publicly facing sites. The Validate Local HTML option sends the current page's HTML to the validator, which works well with pages behind a login, or those that aren't publicly accessible.

You may also want to try View Source Chart (also as FireFox add-on). An interesting note there:

Q. Why does View Source Chart change my XHTML tags to HTML tags?

A. It doesn't. The browser is making these changes, VSC merely displays what the browser has done with your code. Most common: self closing tags lose their closing slash (/). See this article on Rendered Source for more information (archive.org).

The below javascript code snippet will get you the complete ajax rendered HTML generated source. Browser independent one. Enjoy :)

function outerHTML(node){
    // if IE, Chrome take the internal method otherwise build one as lower versions of firefox
        //does not support element.outerHTML property
  return node.outerHTML || (
      function(n){
          var div = document.createElement('div'), h;
          div.appendChild( n.cloneNode(true) );
          h = div.innerHTML;
          div = null;
          return h;
      })(node);
  }


 var outerhtml = outerHTML(document.getElementsByTagName('html')[0]);
var node = document.doctype;
var doctypestring="";
if(node)
{
     // IE8 and below does not have document.doctype and you will get null if you access it.

 doctypestring = "<!DOCTYPE "
         + node.name
         + (node.publicId ? ' PUBLIC "' + node.publicId + '"' : '')
         + (!node.publicId && node.systemId ? ' SYSTEM' : '') 
         + (node.systemId ? ' "' + node.systemId + '"' : '')
         + '>';
         }
         else

         {

             // for IE8 and below you can access doctype like this

         doctypestring = document.all[0].text;
         }
doctypestring +outerhtml ;