To prevent default save of form in Dynamics crm using javascript

To stop the save event in Javascript all you need is this

event.returnValue = false;

Tanguy the CRM tool guy (and CRM MVP) put something very interesting in the comments but I thought I would promote it to this very small blog post

The new method in CRM 2011 is the following one:

Xrm.Page.context.getEventArgs().preventDefault();

preventDefault : Cancels the save operation, but all remaining handlers for the event will still be executed.