<view class='box1' style='width: {{ sysW * 7 }}px'>
 <view class='dateBox'>{{ year }} - {{ month}}</view>
 <block wx:for='{{ weekArr }}'>
  <view style='width: {{ sysW }}px; height: {{ sysW }}px; line-height: {{ sysW }}px;'>{{ item }}</view>
 </block>
 <block wx:for='{{ arr }}'>
  <view style='{{ index == 0 "margin-left:" + sysW * marLet + "px;" : "" }}width: {{ sysW }}px; height: {{ sysW }}px; line-height: {{ sysW }}px;' class='{{ item == getDate "dateOn" : ""}}'>{{ item }}</view>
 </block>
</view>

.box1 .dateBox{
 width: 100%;
 height: 50px;
 line-height: 50px;
 text-align: center;
 margin-top: 20px;
 font-size: 40rpx;
}

.box1{
 display: flex;
 flex-wrap: wrap;
 margin: 0 auto;
}

.box1>view{
 height: 30px;
 line-height: 30px;
 text-align: center;
 font-size: 34rpx;
}

.dateOn{
 border-radius: 50%;
 background-color: hotpink;
 color: #fff;
}

// page/index/index.js
Page({

 /**
  * 页面的初始数据
  */
 data: {
  arr: [],
  sysW: null,
  lastDay: null,
  firstDay: null,
  weekArr: ['日', '一', '二', '三', '四', '五','六'],
  year: null
 },

 //获取日历相关参数
 dataTime: function () {
  var date = new Date();
  var year = date.getFullYear();
  var month = date.getMonth() ;
  var months = date.getMonth() + 1;

  //获取现今年份
  this.data.year = year;

  //获取现今月份
  this.data.month = months;

  //获取今日日期
  this.data.getDate = date.getDate();

  //最后一天是几号
  var d = new Date(year, months, 0);
  this.data.lastDay = d.getDate();

  //第一天星期几
  let firstDay = new Date(year, month, 1);
  this.data.firstDay = firstDay.getDay();
 },

 onLoad: function (options) {
  this.dataTime();

  //根据得到今月的最后一天日期遍历 得到所有日期
  for (var i = 1; i < this.data.lastDay + 1; i++) {
   this.data.arr.push(i);
  }
  var res = wx.getSystemInfoSync();
  this.setData({
   sysW: res.windowHeight / 12,//更具屏幕宽度变化自动设置宽度
   marLet: this.data.firstDay,
   arr: this.data.arr,
   year: this.data.year,
   getDate: this.data.getDate,
   month: this.data.month
  });
 }
})