本文基于react-native 本人在用react-native写一个关于课程表的APP时需要课程表按照日期周期显示，网上查了许多方法，都没有达到自己想要的效果，根据一些方法的参考，再根据自己思维写出自己想要的效果 获取每月有几周 getWeeks(year, month) { var d = new Date(); // 该月第一天 d.setFullYear(year, month-1, 1); var w1 = d.getDay(); if (w1 == 0) w1 = 7; // 该月天数 d.setFullYear(year, month, 0); var dd = d.getDate(); // 第一个周一 let d1; if (w1 != 1) d1 = 7 - w1 + 2; else d1 = 1; let week_count = Math.ceil((dd-d1+1)/7); return week_count; } 根据年月周获取该周从周一到周日的日期 getWeekTime(year, month,weekday) { var d = new Date(); // 该月第一天 d.setFullYear(year, month-1, 1); var w1 = d.getDay(); if (w1 == 0) w1 = 7; // 该月天数 d.setFullYear(year, month, 0); var dd = d.getDate(); // 第一个周一 let d1; if (w1 != 1) d1 = 7 - w1 + 2; else d1 = 1; var monday = d1+(weekday-1)*7; var sunday = monday + 6; var from = year+"-"+month+"-"+monday; var to; if (sunday <= dd) { to = year+"-"+month+"-"+sunday; } else { d.setFullYear(year, month-1, sunday); let days=d.getDate(); to = d.getFullYear()+"-"+(d.getMonth()+1)+"-"+days; } console.log(weekday+" 从" + from + " 到 " + to + ""); } 获取每月第几周的周一的日期 getMondayTime(year, month,weekday) { var d = new Date(); // 该月第一天 d.setFullYear(year, month-1, 1); var w1 = d.getDay(); if (w1 == 0) w1 = 7; // 该月天数 d.setFullYear(year, month, 0); var dd = d.getDate(); // 第一个周一 let d1; if (w1 != 1) d1 = 7 - w1 + 2; else d1 = 1; var monday = d1+(weekday-1)*7; return monday; } 获取周一的日期 getMonDate() { var d=new Date(), day=d.getDay(), date=d.getDate(); if(day==1) return d; if(day==0) d.setDate(date-6); else d.setDate(date-day+1); return d; } 获得周期名字 getDayName(day) { var day=parseInt(day); if(isNaN(day) || day<0 || day>6) return false; var weekday=["周日","周一","周二","周三","周四","周五","周六"]; return weekday[day]; } 获得当前日期在当月第几周 //不包括跟上个月重合的部分 getMonthWeek(a, b, c) { var date = new Date(a, parseInt(b) - 1, c), w = date.getDay(), d = date.getDate(); return Math.ceil( (d + 6 - w) / 7 ); } 获取当月最后一天日期 getLastDay(year,month) { var new_year = year; //取当前的年份 var new_month = month++;//取下一个月的第一天，方便计算（最后一天不固定） if(month>12) { new_month -=12; //月份减 new_year++; //年份增 } var new_date = new Date(new_year,new_month,1); //取当年当月中的第一天 return (new Date(new_date.getTime()-1000*60*60*24)).getDate();//获取当月最后一天日期 } 根据当前日期获取改天所在周，若该月1号是周一，归为上个月最后一周
```
//当前日期几月第几周
showDate(){
var that=this;
var d=this.getMonDate();
var ds=new Date();
var arr=[];
for(var i=0; i<7; i++) {
let weekDay=this.getDayName(d.getDay());
let date=d.getDate()+'日';
if(weekDay=='周一'){
let beginTime=ds.getFullYear()+'-'+(d.getMonth()+1)+'-'+d.getDate();
that.state.beginTime = beginTime;
}
if(weekDay=='周日'){
let endTime=ds.getFullYear()+'-'+(d.getMonth()+1)+'-'+d.getDate();
that.state.endTime = endTime;
}
arr.push({weekDay:weekDay,date:date});
d.setDate(d.getDate()+1);
}
let month=ds.getMonth()+1;
let weeks=this.getMonthWeek(ds.getFullYear(),month,ds.getDate())-1;
//每月周一日期
let oneDate=that.getMondayTime(ds.getFullYear(),month,1);
if(ds.getDate()<oneDate){
month=ds.getMonth();
weeks=this.getWeeks(ds.getFullYear(),month);
}
console.log('month:',month,'weeks:',weeks)
}