Copy another textbox value in real time Jquery

Question

I want to get the value of another textbox and input it in realtime into the other textbox. HOW CAN I DETECT IF TEXT_3 WAS CHANGED? IF TEXT_3 VALUE CHANGED, IT MUST BE INPU

Answer 1

The problem is that you can't bind special event to check that the textbox value was changed using JavaScript and not manually. To solve the task, one option is to use the same keyup event for both text_1 and text_2. JQuery will add the new handler to the existing handlers:

$("#text_1, #text_2").keyup(function(){
    $("#text_4").val($("#text_3").val());
})

DEMO: http://jsfiddle.net/8eXRx/11/