使用JavaScript的通用类对象侦听器遇到麻烦了吗？

Question

I have the following Javascript:

function save_data_check(e) {
    var input_value = $('.input-right').text();

    if (input_value !== "") {

        if(!e) e = window.event;
        e.cancelBubble = true;
        e.returnValue = 'You have unsaved data on this page.'; 

        if (e.stopPropagation) {
        e.stopPropagation();
        e.preventDefault();

        }

    }

}

window.onbeforeunload = save_data_check;

The intended function of this code is to run the function 'save_data_check' when the user tries to leave the page if any input with the common class 'input-right' has any value.

The problem with this function seems to be the most basic part of it: the event listener. Removing the if statement checking if there is any value to the common-class inputs yields the pop-up everytime I try to leave the page?

How am I failing to listen to this event?

Answer 1

There are two problems:

1. onbeforeunload is an unusual event. You simply return the message you want displayed.

2. input elements don't have text, they have a value .

So:

function save_data_check() {
    var msg;

    $('.input-right').each(function() {
        if (this.value) {
            msg = 'You have unsaved data on this page.';
            return false;
        }
    });

    return msg;
}

window.onbeforeunload = save_data_check;

Live Example