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Set validation action for required fields in html-form

What I try to achieve

I try to create a form with required fields. If the user submits the form without filling out all submitted fields, the field-border should become red and the standard message “Please fill out this field” shouldn’t appear.

The following form is a minimal working example:

<!DOCTYPE html>
<html lang='en'>
<head>
    <title>Test</title>
</head>
<body>
    <div class='inner'>
        <form method='POST' action='php/send.php' class='input'>
            <label>Your Name:</label><br>
            <input type='text' name='myName' placeholder='Name' required oninvalid='invalid(this)'/><br><br>
            <label>Your Email:</label><br>
            <input type='email' name='myEmail' placeholder='E-Mail' required oninvalid='invalid(this)'/><br><br>

            <label>Message:</label><br>
            <textarea rows='8' name='myMessage' id='myMessage' placeholder='Message' required oninvalid='invalid(this)'></textarea><br><br>
            <input type='submit' value='Send'/>
        </form>
    </div>
</body>
</html>

What I’ve tried

I’ve tried to set the custom validation message to an empty string:

function invalid(e) {
    e.setCustomValidity('');
    e.style.border = '3px solid red';
}

This does not work (in firefox and in chrome).


I’ve also read somewhere (unfortunately I can’t find the link anymore) that I have to set it to just one space:

function invalid(e) {
    e.setCustomValidity(' ');
    e.style.border = '3px solid red';
}

This does work with chrome, but unfortunately it doesn’t work with firefox (the message-box still appears with one space in it).


I’ve finally tried to just prevent the default:

function invalid(e) {
    e.preventDefault();
    e.style.border = '3px solid red';
}

This doesn’t work with firefox and chrome.

Question

Is it possible to prevent the appearance of the message-error entirely for all browsers?

Answer

Although the answer by Raul Marquez is working, I want to share my own solution:

<!DOCTYPE html>
<html lang='en'>
<head>
    <title>Test</title>
</head>
<body>
    <div class='inner'>
        <form method='POST' action='php/send.php' class='input'>
            <label>Your Name:</label><br>
            <input class='validInput' type='text' name='myName' placeholder='Name' required/><br><br>
            <label>Your Email:</label><br>
            <input class='validInput' type='email' name='myEmail' placeholder='E-Mail' required/><br><br>

            <label>Message:</label><br>
            <textarea class='validInput' rows='8' name='myMessage' id='myMessage' placeholder='Message' required></textarea><br><br>
            <input class='validInput' type='submit' value='Send'/>
        </form>
    </div>
    <script>
        //Get an array of elements with classname 'validInput'
        let elements = document.getElementsByClassName('validInput');

        //iterate over the elements
        for(let i = 0; i < elements.length; i++) {

            //When user focuses on one element (clicks on that element and writes something)
            elements[i].addEventListener('focus', function() {
                this.style.border = '3px solid green';
            });

            //When user stops focusing on an element
            elements[i].addEventListener('blur', function() {
                this.style.border = '1px solid #f3f3f3';
            });

            //When user submits the form and the field-value is invalid
            elements[i].addEventListener('invalid', function(event) {
                event.preventDefault();
                this.style.border = '3px solid red';
            });
        }
    </script>
</body>
</html>