JSFiddle - React, Tailwind, and code Playground
JavaScript
var monthNames = "Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec".split(",");
function isvalid(str) {
var d = new Date(str);
var dateParts = str.split(" ");
return monthNames[d.getMonth()]===dateParts[0] &&
d.getDate()===parseInt(dateParts[1],10) &&
d.getFullYear()===parseInt(dateParts[2],10);
}
alert(isvalid("Jan 14, 2012"));
alert(isvalid("Feb 29, 2011"));