onListBeforeDrag

fires before the mouse button is pressed and the cursor is moved over a draggable item

boolean onListBeforeDrag(object context,Event ev,object list);

context	object	drag-n-drop context object with a set of properties (see details)
ev	Event	a native event object
list	object	the list object where the event has happened

boolean

returning false will prevent dragging of the element

$$("myBoard").attachEvent("onListBeforeDrag", function(context,ev,list){
    if(...){
        return false;
    }
    return true;
});

Details

The properties of the context object are:

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