一、若获取指定日期区间范围，并日期格式化输出则：

python：

import pandas as pd

def get_data():
    a = pd.date_range(start='20170101', end='20170110')
    print(a.strftime("%Y-%m-%d").values.tolist())

def main():
    get_data()

if __name__ == "__main__":
    main()

输出： 

['2017-01-01', '2017-01-02', '2017-01-03', '2017-01-04', '2017-01-05', '2017-01-06', '2017-01-07', '2017-01-08', '2017-01-09', '2017-01-10']

二、指定年月，获取该月份所有日期：

python：

import datetime
import calendar
import pandas as pd

def get_data():
    # a = pd.date_range(start='20170101', end='20170110')
    summary_date_specify = '2021-01-01'
    specify_day = datetime.datetime.strptime(summary_date_specify, "%Y-%m-%d")
    a = pd.date_range(start=datetime.datetime(specify_day.year, specify_day.month, 1), end=datetime.datetime(specify_day.year, specify_day.month, calendar.monthrange(specify_day.year, specify_day.month)[1]))
    print(a.strftime("%Y-%m-%d").values.tolist())

JS（参考自：获取指定年月的全部日期放入数组_weixin_30763455的博客-CSDN博客）

var month = (new Date).getMonth()+1;  //获取当前月
var year = (new Date).getFullYear();　　//获取当前年
var data= [];　　//新建日期数组
var dataLength = new Date(year,month).toJSON().substring(0,10).split("-")[2];   //获取当前年月日期最大值
for (var i = 0; i < dataLength ; i++) {
    var day = i+1;
    if(day>0 && day<10){
        day = '0'+ day 
    }
    data.push(year+'-'+month+'-'+day);  //存入数组
}
console.log(data);

输出：

["2021-11-01","2021-11-02","2021-11-03","2021-11-04","2021-11-05","2021-11-06","2021-11-07","2021-11-08","2021-11-09","2021-11-10","2021-11-11","2021-11-12","2021-11-13","2021-11-14","2021-11-15","2021-11-16","2021-11-17","2021-11-18","2021-11-19","2021-11-20","2021-11-21","2021-11-22","2021-11-23","2021-11-24","2021-11-25","2021-11-26","2021-11-27","2021-11-28","2021-11-29","2021-11-30"]