caimei-authentic-www/utils/index.js

// 绘制logo
export function drawLogo(text = '', len = 4) {
  if (text.length > 4) {
    text = text.split('').filter((item) => /^[\u4E00-\u9FA5]+$/.test(item))
  }

  if (!document) return

  const canvas = document.createElement('canvas')

  canvas.width = 400
  canvas.height = 400

  if (canvas.getContext) {
    // 绘制流程
    var ctx = canvas.getContext('2d')
    ctx.fillStyle = '#130f40'
    ctx.fillRect(0, 0, 400, 400)
    // 绘制第一个字
    ctx.fillStyle = '#eee'
    ctx.font = '80px 黑体'

    text[0] && ctx.fillText(text[0], 80, 160)
    text[1] && ctx.fillText(text[1], 220, 160)
    text[2] && ctx.fillText(text[2], 80, 300)
    text[3] && ctx.fillText(text[3], 220, 300)
  }
  return canvas.toDataURL()
}

// 跳转到授权页面
export function toAuthorization(appId) {
  window.location.href = `https://open.weixin.qq.com/connect/oauth2/authorize?appid=${appId}&redirect_uri=${encodeURIComponent(
    process.env.VUE_APP_LOCAL + '/#/code'
  )}&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirect`
}

/** 时间格式化
 * @param {dateTime} date 标准时间格式 -> new Date()
 * @param {string} format 时间格式化的格式 'yyyy-MM-dd hh:mm:ss'
 * @returns {string} 格式化后的时间  '2017-01-01 01:00:00'
 */
export function dateFormat(date = new Date(), format = 'yyyy-MM-dd hh:mm:ss') {
  var o = {
    'M+': date.getMonth() + 1, // month
    'd+': date.getDate(), // day
    'h+': date.getHours(), // hour
    'm+': date.getMinutes(), // minute
    's+': date.getSeconds(), // second
    'q+': Math.floor((date.getMonth() + 3) / 3), // quarter
    S: date.getMilliseconds(), // millisecond
  }
  if (/(y+)/.test(format)) {
    format = format.replace(
      RegExp.$1,
      (date.getFullYear() + '').substr(4 - RegExp.$1.length)
    )
  }
  for (var k in o) {
    if (new RegExp('(' + k + ')').test(format)) {
      format = format.replace(
        RegExp.$1,
        RegExp.$1.length === 1 ? o[k] : ('00' + o[k]).substr(('' + o[k]).length)
      )
    }
  }
  return format
}

/**
 * @param {string} url
 * @returns {Object}
 */
export function getQueryObject(url) {
  url = url == null ? window.location.href : url
  const search = url.substring(url.lastIndexOf('?') + 1)
  const obj = {}
  const reg = /([^?&=]+)=([^?&=]*)/g
  search.replace(reg, (rs, $1, $2) => {
    const name = decodeURIComponent($1)
    let val = decodeURIComponent($2)
    val = String(val)
    obj[name] = val
    return rs
  })
  return obj
}

/**
 * 防抖
 * @param {Function} func 需要包装的函数
 * @param {string} wait 等待执行时间
 * @param {string} immediate 是否是立即执行 默认不立即执行
 * @returns {Function} 返回包装后的函数
 */
export function debounce(func, wait, immediate) {
  let timeout, result
  return function () {
    const context = this
    const args = arguments
    if (timeout) clearTimeout(timeout)
    if (immediate) {
      const callNow = !timeout
      timeout = setTimeout(function () {
        timeout = null
      }, wait)
      if (callNow) result = func.apply(context, args)
    } else {
      timeout = setTimeout(function () {
        func.apply(context, args)
      }, wait)
    }
    return result
  }
}

// 生成a标签下载文件
export function downloadUrlLink(url) {
  console.log(url)
  const a = document.createElement('a')
  a.setAttribute('download', true)
  a.setAttribute('href', url)
  a.setAttribute('target', '_blank')
  a.style.display = 'none'
  document.body.appendChild(a)
  a.click()
  document.body.removeChild(a)
}