javascript不能判断日期相等

if   (d1.toString()==d2.toString())   alert(true);

alert   (Date.parse(d1)==Date.parse(d2));

 

js日期生成

 

var showDateStr =document.BeForm.showDateStr.value;

var showDateS = showDateStr.split("-");

var showDate = new Date(showDateS[0],showDateS[1]-1,showDateS[2],0,0);