Date.js converte String to a date code example
Example 1: js string to date
var myDate = new Date("2013/1/16");
var str = "2013/1/16";
var strToDate = new Date(str);
Example 2: string date to date in javascript
var ts = '1471793029764';
ts = Number(ts); // cast it to a Number
var date = new Date(ts); // works
var invalidDate = new Date('1471793029764'); // does not work. Invalid Date