javascript - Form is still submitted even though listener function returns false - Stack Overflow

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I'm trying to figure out why this JavaScript doesn't stop the form from being submitted:

<form action="" id="form">
    <input type="text" />
    <input type="submit" />
</form>

<script>
var code = function () {
    return false;
};
var element = window.document.getElementById("form");
if (element.addEventListener) {
    element.addEventListener("submit", code, false);
}
</script>

Unless I add the following onsubmit attribute to the form element:

<form action="" id="form" onsubmit="return false">
    <input type="text" />
    <input type="submit" />
</form>

<script>
var code = function () {
    return false;
};
var element = window.document.getElementById("form");
if (element.addEventListener) {
    element.addEventListener("submit", code, false);
}
</script>

Seems like the addEventListener method alone should do the trick. Any thoughts? I'm on a Mac and I'm experiencing the same result on Safari, Firefox and Opera. Thanks.

I'm trying to figure out why this JavaScript doesn't stop the form from being submitted:

<form action="http://www.example.com" id="form">
    <input type="text" />
    <input type="submit" />
</form>

<script>
var code = function () {
    return false;
};
var element = window.document.getElementById("form");
if (element.addEventListener) {
    element.addEventListener("submit", code, false);
}
</script>

Unless I add the following onsubmit attribute to the form element:

<form action="http://www.example.com" id="form" onsubmit="return false">
    <input type="text" />
    <input type="submit" />
</form>

<script>
var code = function () {
    return false;
};
var element = window.document.getElementById("form");
if (element.addEventListener) {
    element.addEventListener("submit", code, false);
}
</script>

Seems like the addEventListener method alone should do the trick. Any thoughts? I'm on a Mac and I'm experiencing the same result on Safari, Firefox and Opera. Thanks.

• javascript
• forms
• addeventlistener
• onsubmit

Share Improve this question Follow asked Jun 8, 2009 at 23:12 GR1000GR1000 1

• possible duplicate of return false on addEventListener submit still submits the form? – unor Commented Sep 16, 2013 at 11:40

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3 Answers 3

Sorted by: Reset to default 8

Combined the information from the two very helpful answers into a solution that works on both Mac and PC:

<script>
var code = function (eventObject) {
    if (eventObject.preventDefault) {
        eventObject.preventDefault();
    } else if (window.event) /* for ie */ {
        window.event.returnValue = false;
    }
    return true;
};
var element = window.document.getElementById("form");
if (element.addEventListener) {
    element.addEventListener("submit", code, false);
} else if (element.attachEvent) {
    element.attachEvent("onsubmit", code);
}
</script>

Looks like if you change your function to

var code = function(e) {
    e.preventDefault();
}

It should do what you're looking for.

source

I think what you're looking for is the preventDefault() method of the Event interface for browsers that implement it. It will cancel the form submission in the way you expected "return false" to.

More here and here.

<script type="text/javascript">
 var code = function (evt) {
            if (evt.preventDefault) {
                evt.preventDefault();
            }
            return false;
};
window.onload = function() {
    var element = window.document.getElementById("form");
    if (element.addEventListener) {
        element.addEventListener("submit", code, false);
    }
};
</script>

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