Question

How can I detect if the value of a textarea changes using jQuery? I’m currently using keyup() but this triggers every key stroke of course, I dont want my code to run if it’s an arrow key that was pressed or any other key that doesn’t have an impact on the value of the textarea.

Take a look:

$('textarea').keyup(function() {
     if (content was changed)
         // Do something
});

I hope you understand. How can I do this the best way? I don’t want to compare the current value to an old value to check for changes, I hope that’s not the only way.

Answer 1

By all means the easiest way is to store old values to data and do the check every keyup. The solution is quite short and will work in any case. No need to reinvent the wheel.

$("textarea").data("oldValue", function() {
    return this.value;
}).keyup(function() {
    var $this = $(this);
    if (this.value !== $this.data("oldValue")) {
        // Do something

        $this.data("oldValue", this.value);
    }
});

DEMO: http://jsfiddle.net/vvbSj/