JavaScript formatar data em tempo real

by Salustiano Silva

HTML

<input value="" onblur="formatDate(this)" onkeyup="this.value=this.value.replace(/\-/g,'/')">

JavaScript

function formatDate (field) {
    var date = new Date(field.value);
    var year = date.getFullYear(), month = (date.getMonth() + 1), day = date.getDate();
    if (month < 10) month = "0" + month;
    if (day < 10) day = "0" + day;

    field.value = year + "-" + month + "-" + day;   
}