window.showModalDialog vs. window.open

Question

What are situation when you want to use window.showModalDialog function? It seams that you can do exactly the same with window.open function and few parameters that remove some of the chrome (navigation, addressbar, etc...)

When would you want to use window.showModalDialog and window.open?

Answer 1

It has been a few years since this question was originally asked and things have changed a bit since then. window.showModalDialog is now officially standardized as part of HTML5 and is supported in IE, Firefox 3+, Chrome (albeit buggy), and Safari 5.1+.

Unfortunately window.showModalDialog is still plagued by a number of issues.

• Modal dialogs are blocked as popups by default in Firefox, Chrome, and Safari.
• The modal dialogs in Chrome are buggy and aren't truly modal - see http://code.google.com/p/chromium/issues/detail?id=16045 & http://code.google.com/p/chromium/issues/detail?id=42939.
• All browsers except Chrome block the user from interacting with the entire window (favorites, browser controls, other tabs, etc...) when a modal dialog is up.
• They're a pain to debug because they halt JavaScript execution in the parent window while waiting for the modal dialog to complete.
• No mobile browsers support window.showModalDialog.

Therefore it's still not a good idea to use window.showModalDialog. If you need the window opened to be modal (i.e. the user cannot interact with the rest of the page until they deal with the dialog) I would suggest using jQuery UI's dialog plugin.

window.open will work for non modal windows but I would stick with jQuery UI's dialog because opening new windows tends to annoy users.

If you're interested I write about this in more detail on my blog - http://tjvantoll.com/2012/05/02/showmodaldialog-what-it-is-and-why-you-should-never-use-it/.