Disable pasting text into HTML form

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Is there a way using JavaScript to disable the ability to paste text into a text field on an HTML form?

E.g. I have a simple registration form where the user is required to input their email twice. The second email entry is to verify there are no typos in the first email entry. However if the user copy/pastes their email then that defeats the purpose and I've been experiencing users having problems because they've input the wrong email and copy/pasted it.

Maybe I wasn't clear on my question but I am not trying to prevent people from copying (or drag selecting) text on their browser. I just want to stop them from pasting input into a text field to minimize user error.

Perhaps instead of using this "hack" you can suggest another solution to the core problem of what I'm trying to solve here? I've done less than half a dozen user tests and this has already happened twice. My audience does not have a high level of computer proficiency.

javascript html copy-paste

Edit Report

I recently had to begrudgingly disable pasting in a form element. To do so, I wrote a cross-browser* implementation of Internet Explorer's (and others') onpaste event handler. My solution had to be independent of any third-party JavaScript libraries.

Here's what I came up with. It doesn't completely disable pasting (the user can paste a single character at a time, for example), but it meets my needs and avoids having to deal with keyCodes, etc.

// Register onpaste on inputs and textareas in browsers that don't
// natively support it.
(function () {
    var onload = window.onload;

    window.onload = function () {
        if (typeof onload == "function") {
            onload.apply(this, arguments);
        }

        var fields = [];
        var inputs = document.getElementsByTagName("input");
        var textareas = document.getElementsByTagName("textarea");

        for (var i = 0; i < inputs.length; i++) {
            fields.push(inputs[i]);
        }

        for (var i = 0; i < textareas.length; i++) {
            fields.push(textareas[i]);
        }

        for (var i = 0; i < fields.length; i++) {
            var field = fields[i];

            if (typeof field.onpaste != "function" && !!field.getAttribute("onpaste")) {
                field.onpaste = eval("(function () { " + field.getAttribute("onpaste") + " })");
            }

            if (typeof field.onpaste == "function") {
                var oninput = field.oninput;

                field.oninput = function () {
                    if (typeof oninput == "function") {
                        oninput.apply(this, arguments);
                    }

                    if (typeof this.previousValue == "undefined") {
                        this.previousValue = this.value;
                    }

                    var pasted = (Math.abs(this.previousValue.length - this.value.length) > 1 && this.value != "");

                    if (pasted &&am


                        
                        
                            answered 2009-11-12T17:12:07.740

Disable pasting text into HTML form

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