82个常规的前端JavaScript方法封装（51~60）

const getUrlParam = function(name) { // 获取url参数
  let reg = new RegExp('(^|&?)' + name + '=([^&]*)(&|$)', 'i');
  let r = window.location.href.substr(1).match(reg);
  if (r != null) {
    return decodeURI(r[2]);
  }
  return undefined;
}

const store = { // 本地存储
  set: function(name, value, day) { // 设置
    let d = new Date()
    let time = 0
    day = (typeof(day) === 'undefined' || !day) ? 1 : day // 时间,默认存储1天
    time = d.setHours(d.getHours() + (24 * day)) // 毫秒
    localStorage.setItem(name, JSON.stringify({
      data: value,
      time: time
    }))
  },
  get: function(name) { // 获取
    let data = localStorage.getItem(name)
    if (!data) {
      return null
    }
    let obj = JSON.parse(data)
    if (new Date().getTime() > obj.time) { // 过期
      localStorage.removeItem(name)
      return null
    } else {
      return obj.data
    }
  },
  clear: function(name) { // 清空
    if (name) { // 删除键为name的缓存
      localStorage.removeItem(name)
    } else { // 清空全部
      localStorage.clear()
    }
  }
}

const cookie = { // cookie操作【set，get，del】
  set: function(name, value, day) {
    let oDate = new Date()
    oDate.setDate(oDate.getDate() + (day || 30))
    document.cookie = name + '=' + value + ';expires=' + oDate + "; path=/;"
  },
  get: function(name) {
    let str = document.cookie
    let arr = str.split('; ')
    for (let i = 0; i < arr.length; i++) {
      let newArr = arr[i].split('=')
      if (newArr[0] === name) {
        return newArr[1]
      }
    }
  },
  del: function(name) {
    this.set(name, '', -1)
  }
}

const getRealStyle = function(obj, styleName) { // Js获取元素样式【支持内联】
  var realStyle = null
  if (obj.currentStyle) {
    realStyle = obj.currentStyle[styleName]
  } else if (window.getComputedStyle) {
    realStyle = window.getComputedStyle(obj, null)[styleName]
  }
  return realStyle
}

const formatDate = function(fmt, date) { // 时间格式化 【'yyyy-MM-dd hh:mm:ss',时间】
  if (typeof date !== 'object') {
    date = !date ? new Date() : new Date(date)
  }
  var o = {
    'M+': date.getMonth() + 1, // 月份
    'd+': date.getDate(), // 日
    'h+': date.getHours(), // 小时
    'm+': date.getMinutes(), // 分
    's+': date.getSeconds(), // 秒
    'q+': Math.floor((date.getMonth() + 3) / 3), // 季度
    'S': date.getMilliseconds() // 毫秒
  }
  if (/(y+)/.test(fmt)) {
    fmt = fmt.replace(RegExp.$1, (date.getFullYear() + '').substr(4 - RegExp.$1.length))
  }
  for (var k in o) {
    if (new RegExp('(' + k + ')').test(fmt)) {
      fmt = fmt.replace(RegExp.$1, (RegExp.$1.length === 1) ? (o[k]) : (('00' + o[k]).substr(('' + o[k]).length)))
    }
  }
  return fmt
}

const ajax = function(conf) { // ajax操作
  let url = conf.url,
    data = conf.data,
    senData = [], // 封装后的数据
    async = conf.async !== undefined ? conf.async : true, // ture为异步请求
      type = conf.type || 'get', // 默认请求方式get
      dataType = conf.dataType || 'json',
      contenType = conf.contenType || 'application/x-www-form-urlencoded',
      success = conf.success,
      error = conf.error,
      isForm = conf.isForm || false, // 是否formdata
      header = conf.header || {}, // 头部信息
      xhr = '' // 创建ajax引擎对象
  if (data == null) {
    senData = ''
  } else if (typeof data === 'object' && !isForm) { // 如果data是对象，转换为字符串
    for (var k in data) {
      senData.push(encodeURIComponent(k) + '=' + encodeURIComponent(data[k]))
    }
    senData = senData.join('&')
  } else {
    senData = data
  }
  try {
    xhr = new ActiveXObject('microsoft.xmlhttp') // IE内核系列浏览器
  } catch (e1) {
    try {
      xhr = new XMLHttpRequest() // 非IE内核浏览器
    } catch (e2) {
      if (error != null) {
        error('不支持ajax请求')
      }
    }
  };
  xhr.open(type, type !== 'get' ? url : url + '?' + senData, async)
  if (type !== 'get' && !isForm) {
    xhr.setRequestHeader('content-type', contenType)
  }
  for (var h in header) {
    xhr.setRequestHeader(h, header[h])
  }
  xhr.send(type !== 'get' ? senData : null)
  xhr.onreadystatechange = function() {
    if (xhr.readyState === 4) {
      if (xhr.status >= 200 && xhr.status < 300) {
        if (dataType === 'json' && success != null) {
          let res = ''
          try {
            res = eval('(' + xhr.responseText + ')')
          } catch (e) {
            console.log(e)
          }
          success(res) // 将json字符串转换为js对象
        };
      } else {
        if (error != null) {
          error('通讯失败!' + xhr.status)
        }
      }
    }
  }
}

const fetch = function(url, setting) { // fetch请求的封装
  let opts = { // 设置参数的初始值
    method: (setting.method || 'GET').toUpperCase(), // 请求方式
    headers: setting.headers || {}, // 请求头设置
    credentials: setting.credentials || true, // 设置cookie是否一起发送
    body: setting.body || {},
    mode: setting.mode || 'no-cors', // 可以设置 cors, no-cors, same-origin
    redirect: setting.redirect || 'follow', // follow, error, manual
    cache: setting.cache || 'default' // 设置 cache 模式 (default, reload, no-cache)
  }
  let dataType = setting.dataType || 'json' // 解析方式
  let data = setting.data || '' // 参数
  let paramsFormat = function(obj) { // 参数格式
    var str = ''
    for (var i in obj) {
      str += `${i}=${obj[i]}&`
    }
    return str.split('').slice(0, -1).join('')
  }

  if (opts.method === 'GET') {
    url = url + (data ? `?${paramsFormat(data)}` : '')
  } else {
    setting.body = data || {}
  }
  return new Promise((resolve, reject) => {
    fetch(url, opts).then(async res => {
      let data = dataType === 'text' ? await res.text() : dataType === 'blob' ? await res.blob() : await res.json()
      resolve(data)
    }).catch(e => {
      reject(e)
    })
  })
}

const isDevice = function() { // 判断是android还是ios还是web
  var ua = navigator.userAgent.toLowerCase()  if (ua.match(/iPhone\sOS/i) === 'iphone os' || ua.match(/iPad/i) === 'ipad') { // ios
    return 'iOS'
  }  if (ua.match(/Android/i) === 'android') {    return 'Android'
  }  return 'Web'}

const isWx = function() { // 判断是否为微信
  var ua = window.navigator.userAgent.toLowerCase()
  if (ua.match(/MicroMessenger/i) === 'micromessenger') {
    return true
  }
  return false
}

const copyTxt = function(text, fn) { // 复制功能
  if (typeof document.execCommand !== 'function') {
    console.log('复制失败，请长按复制')
    return
  }
  var dom = document.createElement('textarea')
  dom.value = text
  dom.setAttribute('style', 'display: block;width: 1px;height: 1px;')
  document.body.appendChild(dom)
  dom.select()
  var result = document.execCommand('copy')
  document.body.removeChild(dom)
  if (result) {
    console.log('复制成功')
    typeof fn === 'function' && fn()
    return
  }
  if (typeof document.createRange !== 'function') {
    console.log('复制失败，请长按复制')
    return
  }
  var range = document.createRange()
  var div = document.createElement('div')
  div.innerhtml = text
  div.setAttribute('style', 'height: 1px;fontSize: 1px;overflow: hidden;')
  document.body.appendChild(div)
  range.selectNode(div)
  var selection = window.getSelection()
  console.log(selection)
  if (selection.rangeCount > 0) {
    selection.removeAllRanges()
  }
  selection.addRange(range)
  document.execCommand('copy')
  typeof fn === 'function' && fn()
  console.log('复制成功')
}