常用函数封装汇总

常用函数封装

获取某日期若干个工作日后的日期

* 参数: 
*   time: [String] 给定日期 yyyy-MM-dd
*   itervalByDay: [Number] 相隔工作日
* 返回：
*   rq：[String] 匹配的日期yyyy-MM-dd

var getworkday = function(time, itervalByDay){
  var str = time.split("-");
  var date = getDate();
  date.setUTCFullYear(str[0], str[1] - 1, str[2]);
  date.setUTCHours(0, 0, 0, 0);
  var millisceonds =date.getTime();
  for(var i = 1; i <= itervalByDay; i++){
    millisceonds += 24 * 60 * 60 * 1000;
    date.setTime(millisceonds);
    if(date.getDay() == 0 || date.getDay() == 6) i--;
  }
  var year = date.getFullYear();
  var month = (date.getMonth() + 1);
  var day = date.getDate();
  var rq = year + "/" + month + "/" + day;
  return rq;
}

格式化日期

* 参数: 
*   date: 时间戳 [Date]
*   isTime: 是否返回具体时间 [Boolean]
* 返回：
*   isTime: false => yyyy-MM-dd [String]
*   isTime: true => yyyy-MM-dd HH-mm-ss [String]

const formatDate = (date, isTime) => {
  const year = date.getFullYear()
  const month = date.getMonth() + 1
  const day = date.getDate()
  let d = [year, month, day].map(_formatNumber).join('-')
  if (isTime) {
    const hour = date.getHours()
    const minute = date.getMinutes()
    const second = date.getSeconds()
    const time = [hour, minute, second].map(_formatNumber).join(':')

    d = `${d} ${time}`
  }
  return d
}
const _formatNumber = n => {
  n = n.toString()
  return n[1] ? n : '0' + n
}

解析身份证号码信息

* 参数: 
*   IdCard: [String] 身份证号码
*   type: [Number] 1/2/3 
* 返回：
*   type：1 => birthday [String] 出生日期
*   type：2 => sex [Number] 性别
*   type：3 => age [Number] 年龄

formatIdCard (IdCard, type) {
  if (type === 1) {
    // 获取出生日期
    var birthday = IdCard.substring(6, 10) + '-' + IdCard.substring(10, 12) '-' + IdCard.substring(12, 14)
    return birthday
  }
  if (type === 2) {
    // 获取性别
    if (parseInt(IdCard.substr(16, 1)) % 2 === 1) {
      return '1' // 男
    } else {
      return '2' // 女
    }
  }
  if (type === 3) {
    // 获取年龄
    var ageDate = new Date()
    var month = ageDate.getMonth() + 1
    var day = ageDate.getDate()
    var age = ageDate.getFullYear() - IdCard.substring(6, 10) - 1
    if (IdCard.substring(10, 12) < month || IdCard.substring(10, 12) === mont&& IdCard.substring(12, 14) <= day) {
      age++
    }
    if (age <= 0) {
      age = 1
    }
    return age
  }
}

微信小程序wx.request封装

* 1.输出完整接口日志
* 2.统一配置请求头、响应参数
* 3.统一管理请求响应操作（成功、失败、token等情况）

request ({
  url,
  header,
  data = {},
  code = 'errCode', // 接口返回的业务标识
  method = 'POST',
  dataType = 'json',
  timeout = 10000,
  success = () => {},
  fail = () => {},
  complete = () => {}
}) {
  wx.showLoading({ title: '正在加载中', mask: true })
  return wx.request({
    url,
    data,
    method,
    header: {
      'content-type': 'application/json',
      token: this.globalData.token,
      ...header,
    },
    timeout,
    complete: res => {
      wx.hideLoading()
      console.log('');
      console.group(`---- ${url} ----`)
      console.log('Params', data)
      console.log('Header', {
        'content-type': 'application/json',
        token: this.globalData.token,
        ...header,
      })
      console.log('Response', res)
      console.info(`#### ${url} ####`)
      console.groupEnd()
      // token 问题
      if (res.data && res.data.errMsg && (+res.data.errCode === 403 || res.data.errMsg.includes('授权过期请重新登录'))) {
        return this.showError('登录过期，请重新登录', false, () => {
          wx.reLaunch({
            url: `/pages/tab-bar/my/index?errMsg=tokenTimeOut`
          })
        })
      }
      complete(res)
      // // 返回错误信息
      // if (res.data.state && res.data.state !== 'successful') {
      //   wx.showToast({ title: res.data.errMsg, icon: 'none' })
      //   fail(res.data)
      //   return 
      // }
      // success(res.data)
      // 返回成功
      if (res.data && +res.data[code] === 1) {
        if (res.data.state !== 'successful') {
          wx.showToast({ title: res.data.errMsg, icon: 'none' })
          fail(res.data)
          return 
        }
        return success(res.data)
      }
      // 返回错误信息
      wx.showToast({ title: res.data.errMsg, icon: 'none' })
      fail(res.data)
    }
  })
}

获取图片base64

* 参数:
*   file {file object} 文件对象
* 返回:
*   {Promise}

async function imgToBase64 (file) {
  return new Promise(resolve => {
    const reader = new FileReader()
    reader.readAsDataURL(file)
    reader.onload = e => {
      const imgFile = e.target.result
      resolve(imgFile)
    }
  })
}

图片压缩

* 原理: 把图片宽度、高度调小
* @param file {file object | file base64}
* @param {width, height}：压缩图片宽高
* @returns {Promise}
* 
* Tip： 与imgToBase64()配合使用效果更佳

async function imgToCompressed (file, {
  width,
  height
}) {
  if (typeof file === 'object') {
    file = await imgToBase64(file)
  }

  return new Promise(resolve => {
    var image = new Image()
    image.src = file

    image.onload = () => {
      const _width = image.width
      const _height = image.height
      const canvas = document.createElement('canvas')
      const context = canvas.getContext('2d')
      let data = ''
      if (width && width > _width) {
        width = _width
        height = _height
      } else {
        // 等比例缩放
        width = width || Math.floor(_width * height / _height)
        height = height || Math.floor(width * _height / _width)
      }

      canvas.width = width
      canvas.height = height

      context.drawImage(image, 0, 0, width, height)
      data = canvas.toDataURL('image/jpeg').replace('data:image/jpeg;base64,', '')

      resolve(data)
    }
  })
}