Following is my JavaScript (mootools) code:
$('orderNowForm').addEvent('submit', function (event) {
event.preventDefault();
allFilled = false;
$$(".required").each(function (inp) {
if (inp.getValue() != '') {
allFilled = true;
}
});
if (!allFilled) {
$$(".errormsg").setStyle('display', '');
return;
} else {
$$('.defaultText').each(function (input) {
if (input.getValue() == input.getAttribute('title')) {
input.setAttribute('value', '');
}
});
}
this.send({
onSuccess: function () {
$('page_1_table').setStyle('display', 'none');
$('page_2_table').setStyle('display', 'none');
$('page_3_table').setStyle('display', '');
}
});
});
In all browsers except IE, this works fine. But in IE, this causes an error. I have IE8 so while using its JavaScript debugger, I found out that the event
object does not have a preventDefault
method which is causing the error and so the form is getting submitted. The method is supported in case of Firefox (which I found out using Firebug).
Any Help?
in IE, you can use
event.returnValue = false;
to achieve the same result.
And in order not to get an error, you can test for the existence of preventDefault:
if(event.preventDefault) event.preventDefault();
You can combine the two with:
event.preventDefault ? event.preventDefault() : (event.returnValue = false);
if (event.preventDefault) { event.preventDefault(); } else { event.returnValue = false; - sv_in 2009-06-16 10:32
event.preventDefault ? event.preventDefault() : event.returnValue = false;
mortiy 2011-03-06 13:43
event.preventDefault();
stopped working for me in FireFox for some reason, out of the blue. Used mority's code and it worked great. Thanks - James 2012-04-05 18:29
$('.something').click(function(e){ e.preventDefault ? e.preventDefault() : event.returnValue = false; });
Luke 2014-12-18 10:01
If you bind the event through mootools' addEvent function your event handler will get a fixed (augmented) event passed as the parameter. It will always contain the preventDefault() method.
Try out this fiddle to see the difference in event binding. http://jsfiddle.net/pFqrY/8/
// preventDefault always works
$("mootoolsbutton").addEvent('click', function(event) {
alert(typeof(event.preventDefault));
});
// preventDefault missing in IE
<button
id="htmlbutton"
onclick="alert(typeof(event.preventDefault));">
button</button>
For all jQuery users out there you can fix an event when needed. Say that you used HTML onclick=".." and get a IE specific event that lacks preventDefault(), just use this code to get it.
e = $.event.fix(e);
After that e.preventDefault(); works fine.
I know this is quite an old post but I just spent some time trying to make this work in IE8.
It appears that there are some differences in IE8 versions because solutions posted here and in other threads didn't work for me.
Let's say that we have this code:
$('a').on('click', function(event) {
event.preventDefault ? event.preventDefault() : event.returnValue = false;
});
In my IE8 preventDefault()
method exists because of jQuery, but is not working (probably because of the point below), so this will fail.
Even if I set returnValue
property directly to false:
$('a').on('click', function(event) {
event.returnValue = false;
event.preventDefault();
});
This also won't work, because I just set some property of jQuery custom event object.
Only solution that works for me is to set property returnValue
of global variable event
like this:
$('a').on('click', function(event) {
if (window.event) {
window.event.returnValue = false;
}
event.preventDefault();
});
Just to make it easier for someone who will try to convince IE8 to work. I hope that IE8 will die horribly in painful death soon.
UPDATE:
As sv_in points out, you could use event.originalEvent
to get original event object and set returnValue
property in the original one. But I haven't tested it in my IE8 yet.
event.originalEvent
. More Info: http://stackoverflow.com/a/16675056/2255 - sv_in 2013-12-29 14:11
Mootools redefines preventDefault in Event objects. So your code should work fine on every browser. If it doesn't, then there's a problem with ie8 support in mootools.
Did you test your code on ie6 and/or ie7?
The doc says
Every event added with addEvent gets the mootools method automatically, without the need to manually instance it.
but in case it doesn't, you might want to try
new Event(event).preventDefault();
Oh my God! Why IE - sv_in 2009-06-16 10:34
if (e.preventDefault) {
e.preventDefault();
} else {
e.returnValue = false;
}
Tested on IE 9 and Chrome.
To disable a keyboard key after IE9, use : e.preventDefault();
To disable a regular keyboard key under IE7/8, use : e.returnValue = false;
or return false;
If you try to disable a keyboard shortcut (with Ctrl, like Ctrl+F
) you need to add those lines :
try {
e.keyCode = 0;
}catch (e) {}
Here is a full example for IE7/8 only :
document.attachEvent("onkeydown", function () {
var e = window.event;
//Ctrl+F or F3
if (e.keyCode === 114 || (e.ctrlKey && e.keyCode === 70)) {
//Prevent for Ctrl+...
try {
e.keyCode = 0;
}catch (e) {}
//prevent default (could also use e.returnValue = false;)
return false;
}
});
Reference : How to disable keyboard shortcuts in IE7 / IE8
Here's a function I've been testing with jquery 1.3.2 and 09-18-2009's nightly build. Let me know your results with it. Everything executes fine on this end in Safari, FF, Opera on OSX. It is exclusively for fixing a problematic IE8 bug, and may have unintended results:
function ie8SafePreventEvent(e) {
if (e.preventDefault) {
e.preventDefault()
} else {
e.stop()
};
e.returnValue = false;
e.stopPropagation();
}
Usage:
$('a').click(function (e) {
// Execute code here
ie8SafePreventEvent(e);
return false;
})
stop
method before, and I couldn't find it in msdn. What does it do - Oriol 2013-09-23 18:27
.stop()
throws an exception, because it doesn't exist. Any exception will have the desired effect - Jay Bazuzi 2014-06-30 15:35
preventDefault
is a widespread standard; using an adhoc every time you want to be compliant with old IE versions is cumbersome, better to use a polyfill:
if (typeof Event.prototype.preventDefault === 'undefined') {
Event.prototype.preventDefault = function (e, callback) {
this.returnValue = false;
};
}
This will modify the prototype of the Event and add this function, a great feature of javascript/DOM in general. Now you can use e.preventDefault
with no problem.
return false
in your listener should work in all browsers.
$('orderNowForm').addEvent('submit', function () {
// your code
return false;
}
FWIW, in case anyone revisits this question later, you might also check what you are handing to your onKeyPress handler function.
I ran into this error when I mistakenly passed onKeyPress(this) instead of onKeyPress(event).
Just something else to check.
I was helped by a method with a function check. This method works in IE8
if(typeof e.preventDefault == 'function'){
e.preventDefault();
} else {
e.returnValue = false;
}