Detect When Text Is Entered Into The Textarea And Change It Correspondingly

I have a textarea where users can enter or paste email addresses of other people and send them an invite after pressing Submit button. Each email must be seperated with a comma and

Solution 1:

I'm guessing something like this :

var textarea = $('#emails');

textarea.on({
    keyup: function(e) {
        if (e.which === 188) check();
    },
    blur: check    
});

function check() {
    var val  = $.trim(textarea.val()),
        err  = '';

    if (!val.length) {
        err = 'No input ?';
        return;
    }

    var emails   = val.split(','),
        notvalid = [],
        temp     = [];

    $.each(emails, function(_,mail) {
        mail = $.trim(mail);
        if ( mail.length ) {
            var m = mail.match(/([a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+)/gi);
            if (m) {
                temp.push(m);
            }else{
                temp.push(mail);
                notvalid.push(mail)
            }
        }else{
            temp.push(mail);
        }
        if (notvalid.length) err = 'Not valid emails : ' + notvalid.join(', ');
    });

    $('#error').html(err);
    textarea.val((temp.length ? temp : emails).join(', '));
}

FIDDLE

Solution 2:

you can detect when an textarea is changed (or other input field) by using an eventhandler. Jquery supports multiple events (have a look here http://api.jquery.com/category/events/). In this particular case I should use the keyup event for triggering the extractEmails function. This way your extraction will be "live". However, it is also possible by catching a blur or change event.

With keyup eventhandler

http://jsfiddle.net/kasperfish/9hLtW/5/

$('#text').on('keyup',function(event) {
    emails=extractEmails($(this).val());
    $("#emails").text(emails);
});

function extractEmails (text)
{
    return text.match(/([a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+)/gi);
}

Solution 3:

This will convert the entered text to emails when you either lose focus, or enter a comma, as you requested:

function extractEmails (text)
{
    return text.match(/([a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+)/gi);
}

$("#emailtext").on('keypress blur', function(e) {

    if (e.which === 44 || e.type =="blur")
    {
        $('#emails').text(extractEmails($("#emailtext").val()));
    }
});

Here's the fiddle:

http://jsfiddle.net/Mj2KM/