javascript 添加迄今为止的天数，但它显示旧日期月份

Question

我添加了从 2016 年 2 月 19 日开始的 11 天，添加 11 天后，它变成了 2016 年 3 月 1 日，但是当我运行 getMonth() javascript 函数时，它返回二月而不是三月

这是我的代码

var stDate = new Date($("#datepicker1").val()); 
//Fri Feb 19 2016 00:00:00 GMT+0500 (Pakistan Standard Time)
var secondSeasonDays = stDate.setDate(stDate.getDate() + firstSeasonDays);
//firstSeasonDays = 11
var secondSeasonDays = new Date(secondSeasonDays);
// it return  Tue Mar 01 2016 00:00:00 GMT+0500 (Pakistan Standard Time)
var secondSeasonDays = secondSeasonDays.getDate();
var secondSeasonMonth = secondSeasonDays.getMonth();
alert("second season start date is " + secondSeasonDays + " and start month is " + secondSeasonMonth );
// it alerts second season start date is 1 and start month is 2

而 SecondSeasonDaysHere 变量中的日期是 Tue Mar 01 2016 00:00:00 GMT+0500 ，而不是为什么它返回月份为 2 任何建议都会有帮助，提前致谢

Answer 1

The getMonth() method returns the month in the specified date according to local time, as a zero-based value (where zero indicates the first month of the year). The value returned by getMonth() is an integer between 0 and 11. 0 corresponds to January, 1 to February, and so on.

var months = [ "January", "February", "March", "April" .. ];

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