Javascript收集

时间格式化

const formatTime = date => {
  const year = date.getFullYear()
  const month = date.getMonth() + 1
  const day = date.getDate()
  const hour = date.getHours()
  const minute = date.getMinutes()
  const second = date.getSeconds()
  return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')
}

个位数前面填充一个0

const formatNumber = n => {
  n = n.toString()
  return n[1] ? n : '0' + n
}

根据下标删除数组元素

const removeItem = (arr, index) => {
    arr.splice(index, 1)
}

从数组中删除指定的一个元素

const removeItem = (arr, val) => {
    var index = arr.indexOf(val);
    if (index > -1) {
        arr.splice(index, 1);
    }
}

从数组中删除指定的多个元素

const arrRemoves = (arr, val) => {
    var newIndexs = val.map(function(val, idx){return val - idx})
    newIndexs.forEach(function(index){
        arr.splice(index, 1)
    })
}

数组根据对象属性排序

var arr=[{name:"rose", id:3}，{name:"jack"，id:1}，{name:"mafy"id:2}]
function rule(key) {
    return function (a, b) {
        return a[key] - b[key]
    }
}        
arr.sort(rule("id"))

随机打乱数组顺序

var arr = [1, 2, 3, 4, 5, 6];
function randomsort(a, b) {
    return Math.random() > .5 ? -1 : 1
}
arr.sort(randomsort)

手机号码加*号

var phone = 13834236433;
function addStar(phone) {
    return phone.substr(0, 3) + '****' + phone.substr(-4, 4);
}
addStar(phone);

根据数组对象元素id去重

  function uniarr (arr) {
    var hash = [];
    for (var i = 0; i < arr.length; i++) {
      for (var j = i + 1; j < arr.length; j++) {
        if (arr[i].id == arr[j].id) {
          ++i;
        }
      }
      hash.push(arr[i]);
    }
    return hash;
  }

重复字符串N次

  var times = function(str, num) {
    return num > 1 ? str += times(str, --num) : str;
  }

js 实现复制

<textarea id="txt">hello world</textarea>
<script type="text/javascript">
    window.onload = function() {
        var Url2=document.getElementById("txt");
        Url2.select(); // 选择对象
        document.execCommand("Copy"); // 执行浏览器复制命令
        console.log("已复制好，可贴粘。");
    }
</script>

图片流插件

[https://github.com/desandro/masonry](https://github.com/desandro/masonry)

图片轮播图插件

• swiper.js
• 轮播图 [https://github.com/stevenwanderski/bxslider-4](https://github.com/stevenwanderski/bxslider-4)

浏览器拷贝粘贴插件

[拷贝粘贴] (https://github.com/zenorocha/clipboard.js)[https://github.com/zenorocha/clipboard.js](https://github.com/zenorocha/clipboard.js)

在浏览器中打开微信

<a herf="weixin://"></a>

日期选择器

日期选择器 [https://github.com/ddd702/datePicker](https://github.com/ddd702/datePicker)

地址选择器

地址选择器 [https://github.com/nzbin/Framework7-CityPicker](https://github.com/nzbin/Framework7-CityPicker)