2つのDateオブジェクトが同じ日か否かを判定する
date1 = new Date('Tue, 19 Feb 2008 02:26:57 GMT'); date2 = new Date('Tue, 13 Feb 2008 02:26:57 GMT');// date1と日付が違う date3 = new Date('Tue, 19 Feb 2008 02:36:57 GMT');// date1と時刻が違う new Date(date1.toDateString()).getTime() == new Date(date2.toDateString()).getTime(); //false new Date(date1.toDateString()).getTime() == new Date(date3.toDateString()).getTime(); //true