[解決済み] javascript で日付を 'Thu Jun 09 2011 00:00:00 GMT+0530 (India Standard Time)' から 'YYYY-MM-DD' に変換する

function convert(str) {
  var date = new Date(str),
    mnth = ("0" + (date.getMonth() + 1)).slice(-2),
    day = ("0" + date.getDate()).slice(-2);
  return [date.getFullYear(), mnth, day].join("-");
}

console.log(convert("Thu Jun 09 2011 00:00:00 GMT+0530 (India Standard Time)"))
//-> "2011-06-08"

function convert(str) {
  var mnths = {
      Jan: "01",
      Feb: "02",
      Mar: "03",
      Apr: "04",
      May: "05",
      Jun: "06",
      Jul: "07",
      Aug: "08",
      Sep: "09",
      Oct: "10",
      Nov: "11",
      Dec: "12"
    },
    date = str.split(" ");

  return [date[3], mnths[date[1]], date[2]].join("-");
}

console.log(convert("Thu Jun 09 2011 00:00:00 GMT+0530 (India Standard Time)"))
//-> "2011-06-09"