how to format string to date in javascript 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: get date format javascript

//Date format
  const handleDate = (dataD) => {
    let data= new Date(dataD)
    let month = data.getMonth() + 1
    let day = data.getDate()
    let year = data.getFullYear()
    if(day<=9)
      day = '0' + day
    if(month<10)
      month = '0' + month
    const postDate = year + '-' + month + '-' + day
    return postDate
  }