webbrowser - Dave's Blog


[html5] Web Workers: Race-Condition setting onmessage handler?

2011 Sep 20, 7:17There's no race between posting to a web worker and the web worker setting up its message handler as long as the web worker sets its message handler in the first sync. block of code that runs in the web worker: "Basically, once the initial worker script returns, the worker's port is enabled and the normal message port event delivery mechanism kicks in (including dropping unhandled messages on the floor)."PermalinkCommentstechnical web-worker webbrowser programming postMessage

draft-ietf-websec-origin-01 - The Web Origin Concept

2011 Jun 21, 1:22"This document defines the concept of an "origin", which is often used
as the scope of authority or privilege by user agents. Typically,
user agents isolate content retrieved from different origins to
prevent malicious web site operators from interfering with the
operation of benign web sites. In addition to outlining the
principles that underly the origin concept, this document defines how
to determine the origin of a URI, how to serialize an origin into a
string, and an HTTP header, named "Origin", that indicates which
origins are associated with an HTTP request."PermalinkCommentsietf reference technical web browser user-agent webbrowser origin

[whatwg] CORS requests for image and video elements

2011 May 23, 4:26Applying CORS to the media elements: "I've added a content attribute to <img>, <video>, and <audio> that makes the image or media resource be fetched with CORS And have the origin of the page if CORS succeeded. The attribute is "cross-origin" and it has two allowed values, "use-credentials" and "anonymous". The latter is the default, so you can just say <img cross-origin src="data.png">."PermalinkCommentscors crossdomain web browser webbrowser html technical

Chromium Blog: SSL FalseStart Performance Results

2011 May 22, 10:44Links to the IETF draft document of and describes the perf benefits of SSL False Start.PermalinkCommentssecurity google browser web webbrowser https performance ssl tls technical

JavaScript & .NET interop via WebBrowser Control

2011 Apr 5, 10:00

For my GeolocMock weekend project I intended to use the Bing Maps API to display a map in a WebBrowser control and allow the user to interact with that to select a location to be consumed by my application. Getting my .NET code to talk to the JavaScript in the WebBrowser control was surprisingly easy.

To have .NET execute JavaScript code you can use the InvokeScript method passing the name of the JavaScript function to execute and an object array of parameters to pass:

new object[] {

The other direction, having JavaScript call into .NET is slightly more complicated but still pretty easy as far as language interop goes. The first step is to mark your assembly as ComVisible so that it can interact with JavaScript via COM. VS had already added a ComVisible declaration to my project I just had to change the value to true.

[assembly: ComVisible(true)]

Next set ObjectForScripting attribute to the object you want to expose to JavaScript.

this.webBrowser2.ObjectForScripting = this.locationState;

Now that object is exposed as window.external in JavaScript and you can call methods on it.

window.external.Set(lat, long, alt, gUncert);

However you don't seem to be able to test for the existence of methods off of it. For example the following JavaScript generates an exception for me even though I have a Set method:

if (window.external && window.external.Set) {
PermalinkCommentsjavascript webbrowser .net technical csharp

Using client-side storage, today. ✩ Mozilla Hacks – the Web developer blog

2011 Apr 5, 5:14A JS wrapper script that lets you use storage in IE6/7 via userData or localStorage every where else.PermalinkCommentsjavascript html web webbrowser storage technical userdata localstorage

IE9 Document Mode in WebOC

2011 Apr 4, 10:00

Working on GeolocMock it took me a bit to realize why my HTML could use the W3C Geolocation API in IE9 but not in my WebBrowser control in my .NET application. Eventually I realized that I was getting the wrong IE doc mode. Reading this old More IE8 Extensibility Improvements IE blog post from the IE blog I found the issue is that for app compat the WebOC picks older doc modes but an app hosting the WebOC can set a regkey to get different doc modes. The IE9 mode isn't listed in that article but I took a guess based on the values there and the decimal value 9999 gets my app IE9 mode. The following is the code I run in my application to set its regkey so that my app can get the IE9 doc mode and use the geolocation API.

        static private void UseIE9DocMode()
RegistryKey key = null;
key = Registry.CurrentUser.OpenSubKey("Software\\Microsoft\\Internet Explorer\\Main\\FeatureControl\\FEATURE_BROWSER_EMULATION", true);
catch (Exception)
key = Registry.CurrentUser.CreateSubKey("Software\\Microsoft\\Internet Explorer\\Main\\FeatureControl\\FEATURE_BROWSER_EMULATION");
key.SetValue(System.Diagnostics.Process.GetCurrentProcess().MainModule.ModuleName, 9999, RegistryValueKind.DWord);
PermalinkCommentsweboc fck ie document mode technical ie9

Internet Explorer team sent us cake for shipping Firefox 4 #fx4 on Twitpic

2011 Mar 22, 12:51We've now got IE9 and FF4 which means time for more cake!PermalinkCommentshumor browser webbrowser firefox ie ie9 ff4 mozilla microsoft

[whatwg] Proposal for IsSearchProviderInstalled / AddSearchProvider

2011 Feb 23, 2:17Proposal to standardize on the function to add search providers in user agents.PermalinkCommentstechnical search-provider browser webbrowser web whatwg

An Analysis of Browser Domain-Isolation Bugs

2010 Oct 28, 7:49PermalinkCommentsdavid-ross security browser research web webbrowser technical todo system:filetype:pdf system:media:document

Revision 60.000, first bits of the URL API and pingin’ the anchor « Peter Beverloo

2010 Sep 27, 3:08Adam Barth's URI API draft starts to appear in webkit: "One of the things Adam Barth is currently working on is an URL API. Citing it, the API can be used for constructing, parsing and resolving URLs through scripting, easening up tasks like getting and setting parameters. Today the first part landed in WebKit, which added the “origin” property."PermalinkCommentswebkit adam-barth uri url api javascript dom html html5 browser webbrowser technical

Sam Ruby: Chromie Don’t Play That

2009 Sep 24, 3:58"Put more constructively, if GCF mentioned application/xhtml+xml AND intercepted it, my site would “just work”. But that wouldn’t be an “opt in”, a concept that Ian Hickson once described as yet another quirks mode switch."PermalinkCommentschrome google web browser extension webbrowser mime xml xhtml technical

hackademix.net » Strict Transport Security in NoScript

2009 Sep 24, 3:51A proposed new HTTP header 'X-Force-TLS' to indicate a site only wants to be over HTTPS.PermalinkCommentshttp header security https extension noscript web browser webbrowser

Bookmarklet of death: Domain hijacking without 0days | GNUCITIZEN

2009 Sep 23, 7:56"I do understand that it would be annoying to warn users every time they run a bookmarklet, but I think it would be sensible to show a warning at least the first time a given bookmarklet is executed. If you work for a popular web browser vendor such as Microsoft or Mozilla, you can think of this as my wish for the day! I'd love to hear your feedback if you are reading this!"PermalinkCommentstechnical bookmarklet bookmarklets security web webbrowser javascript

HTML 5 - 5.7.2 Custom protocol and content handlers

2009 Apr 7, 10:45HTML 5 allows websites to register themselves as handlers of particular URI schemes and particular content-types. I think this is great, but I'm surprised it doesn't support POSTing files to allow for interactions with local content.PermalinkCommentshtml5 url uri protocol reference html standard javascript webbrowser registerProtocolHandler

Notes on Creating Internet Explorer Extensions in C++ and COM

2009 Mar 20, 4:51

Working on Internet Explorer extensions in C++ & COM, I had to relearn or rediscover how to do several totally basic and important things. To save myself and possibly others trouble in the future, here's some pertinent links and tips.

First you must choose your IE extensibility point. Here's a very short list of the few I've used:

Once you've created your COM object that implements IObjectWithSite and whatever other interfaces your extensibility point requires as described in the above links you'll see your SetSite method get called by IE. You might want to know how to get the top level browser object from the IUnknown site object passed in via that method.

After that you may also want to listen for some events from the browser. To do this you'll need to:

  1. Implement the dispinterface that has the event you want. For instance DWebBrowserEvents2, or HTMLDocumentEvents, or HTMLWindowEvents2. You'll have to search around in that area of the documentation to find the event you're looking for.
  2. Register for events using AtlAdvise. The object you need to subscribe to depends on the events you want. For example, DWebBrowserEvents2 come from the webbrowser object, HTMLDocumentEvents come from the document object assuming its an HTML document (I obtained via get_Document method on the webbrowser), and HTMLWindowEvents2 come from the window object (which oddly I obtained via calling the get_script method on the document object). Note that depending on when your SetSite method is called the document may not exist yet. For my extension I signed up for browser events immediately and then listened for events like NavigateComplete before signing up for document and window events.
  3. Implement IDispatch. The Invoke method will get called with event notifications from the dispinterfaces you sign up for in AtlAdvise. Implementing Invoke manually is a slight pain as all the parameters come in as VARIANTs and are in reverse order. There's some ATL macros that may make this easier but I didn't bother.
  4. Call AtlUnadvise at some point -- at the latest when SetSite is called again and your site object changes.

If you want to check if an IHTMLElement is not visible on screen due how the page is scrolled, try comparing the Body or Document Element's client height and width, which appears to be the dimensions of the visible document area, to the element's bounding client rect which appears to be its position relative to the upper left corner of the visible document area. I've found this to be working for me so far, but I'm not positive that frames, iframes, zooming, editable document areas, etc won't mess this up.

Be sure to use pointers you get from the IWebBrowser/IHTMLDocument/etc. only on the thread on which you obtained the pointer or correctly marshal the pointers to other threads to avoid weird crashes and hangs.

Obtaining the HTML document of a subframe is slightly more complicated then you might hope. On the other hand this might be resolved by the new to IE8 method IHTMLFrameElement3::get_contentDocument

Check out Eric's IE blog post on IE extensibility which has some great links on this topic as well.

PermalinkCommentstechnical boring internet explorer com c++ ihtmlelement extension

Hands on: Google leaps forward with Chrome 2.0 dev. preview

2009 Jan 10, 1:32I'm looking forward to hearing about Chrome's new HTTP stack: "The Chrome developers are moving away from using the WinHTTP library and are working on a platform-neutral alternative that will make Chrome easier to port to other operating systems."PermalinkCommentschrome google http arstechnica web webbrowser browser

Investigation of a Few Application Protocols (Updated)

2008 Oct 25, 6:51

Windows allows for application protocols in which, through the registry, you specify a URL scheme and a command line to have that URL passed to your application. Its an easy way to hook a webbrowser up to your application. Anyone can read the doc above and then walk through the registry and pick out the application protocols but just from that info you can't tell what the application expects these URLs to look like. I did a bit of research on some of the application protocols I've seen which is listed below. Good places to look for information on URI schemes: Wikipedia URI scheme, and ESW Wiki UriSchemes.

Some Application Protocols and associated documentation.
Scheme Name Notes
search-ms Windows Search Protocol The search-ms application protocol is a convention for querying the Windows Search index. The protocol enables applications, like Microsoft Windows Explorer, to query the index with parameter-value arguments, including property arguments, previously saved searches, Advanced Query Syntax, Natural Query Syntax, and language code identifiers (LCIDs) for both the Indexer and the query itself. See the MSDN docs for search-ms for more info.
Example: search-ms:query=food
OneNote OneNote Protocol From the OneNote help: /hyperlink "pagetarget" - Starts OneNote and opens the page specified by the pagetarget parameter. To obtain the hyperlink for any page in a OneNote notebook, right-click its page tab and then click Copy Hyperlink to this Page.
Example: onenote:///\\GUMMO\Users\davris\Documents\OneNote%20Notebooks\OneNote%202007%20Guide\Getting%20Started%20with%20OneNote.one#section-id={692F45F5-A42A-415B-8C0D-39A10E88A30F}&end
callto Callto Protocol ESW Wiki Info on callto
Skype callto info
NetMeeting callto info
Example: callto://+12125551234
itpc iTunes Podcast Tells iTunes to subscribe to an indicated podcast. iTunes documentation.
C:\Program Files\iTunes\iTunes.exe /url "%1"
Example: itpc:http://www.npr.org/rss/podcast.php?id=35
Magnet Magnet URI Magnet URL scheme described by Wikipedia. Magnet URLs identify a resource by a hash of that resource so that when used in P2P scenarios no central authority is necessary to create URIs for a resource.
mailto Mail Protocol RFC 2368 - Mailto URL Scheme.
Mailto Syntax
Opens mail programs with new message with some parameters filled in, such as the to, from, subject, and body.
Example: mailto:?to=david.risney@gmail.com&subject=test&body=Test of mailto syntax
MMS mms Protocol MSDN describes associated protocols.
Wikipedia describes MMS.
"C:\Program Files\Windows Media Player\wmplayer.exe" "%L"
Also appears to be related to MMS cellphone messages: MMS IETF Draft.
secondlife [SecondLife] Opens SecondLife to the specified location, user, etc.
SecondLife Wiki description of the URL scheme.
"C:\Program Files\SecondLife\SecondLife.exe" -set SystemLanguage en-us -url "%1"
Example: secondlife://ahern/128/128/128
skype Skype Protocol Open Skype to call a user or phone number.
Skype's documentation
Wikipedia summary of skype URL scheme
"C:\Program Files\Skype\Phone\Skype.exe" "/uri:%l"
Example: skype:+14035551111?call
skype-plugin Skype Plugin Protocol Handler Something to do with adding plugins to skype? Maybe.
"C:\Program Files\Skype\Plugin Manager\skypePM.exe" "/uri:%1"
svn SVN Protocol Opens TortoiseSVN to browse the repository URL specified in the URL.
C:\Program Files\TortoiseSVN\bin\TortoiseProc.exe /command:repobrowser /path:"%1"
webcal Webcal Protocol Wikipedia describes webcal URL scheme.
Webcal URL scheme description.
A URL that starts with webcal:// points to an Internet location that contains a calendar in iCalendar format.
"C:\Program Files\Windows Calendar\wincal.exe" /webcal "%1"
Example: webcal://www.lightstalkers.org/LS.ics
zune Zune Protocol Provides access to some Zune operations such as podcast subscription (via Zune Insider).
"c:\Program Files\Zune\Zune.exe" -link:"%1"
Example: zune://subscribe/?name=http://feeds.feedburner.com/wallstrip.
feed Outlook Add RSS Feed Identify a resource that is a feed such as Atom or RSS. Implemented by Outlook to add the indicated feed to Outlook.
Feed URI scheme pre-draft document
"C:\PROGRA~2\MICROS~1\Office12\OUTLOOK.EXE" /share "%1"
im IM Protocol RFC 3860 IM URI scheme description
Like mailto but for instant messaging clients.
Registered by Office Communicator but I was unable to get it to work as described in RFC 3860.
"C:\Program Files (x86)\Microsoft Office Communicator\Communicator.exe" "%1"
tel Tel Protocol RFC 5341 - tel URI scheme IANA assignment
RFC 3966 - tel URI scheme description
Call phone numbers via the tel URI scheme. Implemented by Office Communicator.
"C:\Program Files (x86)\Microsoft Office Communicator\Communicator.exe" "%1"
(Updated 2008-10-27: Added feed, im, and tel from Office Communicator)PermalinkCommentstechnical application protocol shell url windows

Old Miscellaneous Thoughts

2007 Dec 26, 5:45Miscellaneous thoughts I had that would have been relevant many months ago:
PermalinkCommentspopfly apple personal history-channel indiana-jones pipes mac technical microsoft mashup yahoo nontechnical

WebBrowser Customization

2007 Oct 5, 1:50How to host a WebBrowser control and customize it to your hearts content.PermalinkCommentsie internet microsoft web browser msdn reference howto webbrowser
Older Entries Creative Commons License Some rights reserved.