VUE知识点小记

.if里面不能用import方式导入,只能用require方式引入

判断长度大于0

  getIssues (vue, data) {
    let label = ''
    if (data.label && data.label.trim().length > ) {
      label = `+label:"${data.label}"`
    }

es6中使用Number.isInteger()用来判断一个值是否为整数。

在html将显示时间格式化：

<span class="time">{{$moment(comment.created_at).format('YYYY-MM-DD HH:mm')}}</span>

回到主页

this.$router.push('/')

 

<span
        @click="openThirdPartySite('https://github.com/bingoogolapple/BGAIssueBlog')">BGAIssueBlog</span>

openThirdPartySite (url) {
        window.open(url)
      }
            visitRoute(r) {
                this.$router.push(r)
            }

<el-table-column prop="sex" label="性别" width="" :formatter="formatSex" sortable>
            </el-table-column>

//性别显示转换
            formatSex: function (row, column) {
                return row.sex ==  ? '男' : row.sex ==  ? '女' : '未知';
            },

return context == null || context == "" || context == "undefined" ? "" : context;

判断指定用户名

export function validUsername(str) {
  const valid_map = ['admin', 'editor']
  return valid_map.indexOf(str.trim()) >=
}

/**
 * @param {string} str
 * @returns {Boolean}
 */
export function isString(str) {
  if (typeof str === 'string' || str instanceof String) {
    return true
  }
  return false
}

/**
 * @param {Array} arg
 * @returns {Boolean}
 */
export function isArray(arg) {
  if (typeof Array.isArray === 'undefined') {
    return Object.prototype.toString.call(arg) === '[object Array]'
  }
  return Array.isArray(arg)
}

utils:

/**
 * Created by PanJiaChen on 16/11/18.
 */

/**
 * Parse the time to string
 * @param {(Object|string|number)} time
 * @param {string} cFormat
 * @returns {string}
 */
export function parseTime(time, cFormat) {
  if (arguments.length === ) {
    return null
  }
  const format = cFormat || '{y}-{m}-{d} {h}:{i}:{s}'
  let date
  if (typeof time === 'object') {
    date = time
  } else {
    if ((typeof time === 'string') && (/^[-]+$/.test(time))) {
      time = parseInt(time)
    }
    if ((typeof time === 'number') && (time.toString().length === )) {
      time = time *
    }
    date = new Date(time)
  }
  const formatObj = {
    y: date.getFullYear(),
    m: date.getMonth() + ,
    d: date.getDate(),
    h: date.getHours(),
    i: date.getMinutes(),
    s: date.getSeconds(),
    a: date.getDay()
  }
  const time_str = format.replace(/{(y|m|d|h|i|s|a)+}/g, (result, key) => {
    let value = formatObj[key]
    // Note: getDay() returns 0 on Sunday
    if (key === 'a') { return ['日', '一', '二', '三', '四', '五', '六'][value ] }
    if (result.length >  && value < ) {
      value = '' + value
    }
    return value ||
  })
  return time_str
}

/**
 * @param {number} time
 * @param {string} option
 * @returns {string}
 */
export function formatTime(time, option) {
  if (('' + time).length === ) {
    time = parseInt(time) *
  } else {
    time = +time
  }
  const d = new Date(time)
  const now = Date.now()

  const diff = (now - d) / 

  if (diff < ) {
    return '刚刚'
  } else if (diff < ) {
    // less 1 hour
    return Math.ceil(diff / ) + '分钟前'
  } else if (diff <  * ) {
    return Math.ceil(diff / ) + '小时前'
  } else if (diff <  *  * ) {
    return '1天前'
  }
  if (option) {
    return parseTime(time, option)
  } else {
    return (
      d.getMonth() +
       +
      '月' +
      d.getDate() +
      '日' +
      d.getHours() +
      '时' +
      d.getMinutes() +
      '分'
    )
  }
}

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

/**
 * @param {string} input value
 * @returns {number} output value
 */
export function byteLength(str) {
  // returns the byte length of an utf8 string
  let s = str.length
  for (var i = str.length - ; i >= ; i--) {
    const code = str.charCodeAt(i)
    if (code > 0x7f && code <= 0x7ff) s++
    else if (code > 0x7ff && code <= 0xffff) s +=
    if (code >= 0xDC00 && code <= 0xDFFF) i--
  }
  return s
}

/**
 * @param {Array} actual
 * @returns {Array}
 */
export function cleanArray(actual) {
  const newArray = []
  for (let i = ; i < actual.length; i++) {
    if (actual[i]) {
      newArray.push(actual[i])
    }
  }
  return newArray
}

/**
 * @param {Object} json
 * @returns {Array}
 */
export function param(json) {
  if (!json) return ''
  return cleanArray(
    Object.keys(json).map(key => {
      if (json[key] === undefined) return ''
      return encodeURIComponent(key) + '=' + encodeURIComponent(json[key])
    })
  ).join('&')
}

/**
 * @param {string} url
 * @returns {Object}
 */
export function param2Obj(url) {
  const search = url.split('?')[]
  if (!search) {
    return {}
  }
  return JSON.parse(
    '{"' +
      decodeURIComponent(search)
        .replace(/"/g, '\\"')
        .replace(/&/g, '","')
        .replace(/=/g, '":"')
        .replace(/\+/g, ' ') +
      '"}'
  )
}

/**
 * @param {string} val
 * @returns {string}
 */
export function html2Text(val) {
  const div = document.createElement('div')
  div.innerHTML = val
  return div.textContent || div.innerText
}

/**
 * Merges two objects, giving the last one precedence
 * @param {Object} target
 * @param {(Object|Array)} source
 * @returns {Object}
 */
export function objectMerge(target, source) {
  if (typeof target !== 'object') {
    target = {}
  }
  if (Array.isArray(source)) {
    return source.slice()
  }
  Object.keys(source).forEach(property => {
    const sourceProperty = source[property]
    if (typeof sourceProperty === 'object') {
      target[property] = objectMerge(target[property], sourceProperty)
    } else {
      target[property] = sourceProperty
    }
  })
  return target
}

/**
 * @param {HTMLElement} element
 * @param {string} className
 */
export function toggleClass(element, className) {
  if (!element || !className) {
    return
  }
  let classString = element.className
  const nameIndex = classString.indexOf(className)
  if (nameIndex === -) {
    classString += '' + className
  } else {
    classString =
      classString.substr(, nameIndex) +
      classString.substr(nameIndex + className.length)
  }
  element.className = classString
}

/**
 * @param {string} type
 * @returns {Date}
 */
export function getTime(type) {
  if (type === 'start') {
    return new Date().getTime() -  *  *  *
  } else {
    return new Date(new Date().toDateString())
  }
}

/**
 * @param {Function} func
 * @param {number} wait
 * @param {boolean} immediate
 * @return {*}
 */
export function debounce(func, wait, immediate) {
  let timeout, args, context, timestamp, result

  const later = function() {
    // 据上一次触发时间间隔
    const last = +new Date() - timestamp

    // 上次被包装函数被调用时间间隔 last 小于设定时间间隔 wait
    if (last < wait && last > ) {
      timeout = setTimeout(later, wait - last)
    } else {
      timeout = null
      // 如果设定为immediate===true，因为开始边界已经调用过了此处无需调用
      if (!immediate) {
        result = func.apply(context, args)
        if (!timeout) context = args = null
      }
    }
  }

  return function(...args) {
    context = this
    timestamp = +new Date()
    const callNow = immediate && !timeout
    // 如果延时不存在，重新设定延时
    if (!timeout) timeout = setTimeout(later, wait)
    if (callNow) {
      result = func.apply(context, args)
      context = args = null
    }

    return result
  }
}

/**
 * This is just a simple version of deep copy
 * Has a lot of edge cases bug
 * If you want to use a perfect deep copy, use lodash's _.cloneDeep
 * @param {Object} source
 * @returns {Object}
 */
export function deepClone(source) {
  if (!source && typeof source !== 'object') {
    throw new Error('error arguments', 'deepClone')
  }
  const targetObj = source.constructor === Array ? [] : {}
  Object.keys(source).forEach(keys => {
    if (source[keys] && typeof source[keys] === 'object') {
      targetObj[keys] = deepClone(source[keys])
    } else {
      targetObj[keys] = source[keys]
    }
  })
  return targetObj
}

/**
 * @param {Array} arr
 * @returns {Array}
 */
export function uniqueArr(arr) {
  return Array.from(new Set(arr))
}

/**
 * @returns {string}
 */
export function createUniqueString() {
  const timestamp = +new Date() + ''
  const randomNum = parseInt(( + Math.random()) * ) + ''
  return (+(randomNum + timestamp)).toString()
}

/**
 * Check if an element has a class
 * @param {HTMLElement} elm
 * @param {string} cls
 * @returns {boolean}
 */
export function hasClass(ele, cls) {
  return !!ele.className.match(new RegExp('(\\s|^)' + cls + '(\\s|$)'))
}

/**
 * Add class to element
 * @param {HTMLElement} elm
 * @param {string} cls
 */
export function addClass(ele, cls) {
  if (!hasClass(ele, cls)) ele.className += ' ' + cls
}

/**
 * Remove class from element
 * @param {HTMLElement} elm
 * @param {string} cls
 */
export function removeClass(ele, cls) {
  if (hasClass(ele, cls)) {
    const reg = new RegExp('(\\s|^)' + cls + '(\\s|$)')
    ele.className = ele.className.replace(reg, ' ')
  }
}

https://github.com/PanJiaChen/vue-element-admin.git