js 工具函数

1. 获取url中传参的值

function getParam (name) {
    var reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)', 'i');
    var r=window.location.search.substr(1).replace(new RegExp(/(amp;)/g),'').match(reg);
    if (r != null) {
        return r[2];
    }
    return null;
};

2. 判断变量的数据类型

function typeOf(obj) {
    const toString = Object.prototype.toString;
    const map = {
    '[object Boolean]'  : 'boolean',
    '[object Number]'   : 'number',
    '[object String]'   : 'string',
    '[object Function]' : 'function',
    '[object Array]'    : 'array',
    '[object Date]'     : 'date',
    '[object RegExp]'   : 'regExp',
    '[object Undefined]': 'undefined',
    '[object Null]'     : 'null',
    '[object Object]'   : 'object'
    };
    return map[toString.call(obj)];
},

3. 深度克隆对象或数组,多个对象或数组嵌套

      deepCopy(data) {
        const t = this.typeOf(data);
        let o;

        if (t === 'array') {
          o = [];
        } else if ( t === 'object') {
          o = {};
        } else {
          return data;
        }

        if (t === 'array') {
          for (let i = 0; i < data.length; i++) {
            o.push(this.deepCopy(data[i]));
          }
        } else if ( t === 'object') {
          for (let i in data) {
            o[i] = this.deepCopy(data[i]);
          }
        }
        return o;
      },

4. 节流函数

debounce(func, delay) {

    let timer;

    return function (...args) {
        if (timer) {
            clearTimeout(timer);
        }

    timer = window.setTimeout(() => {
        func.apply(this, args);
    }, delay);
    }

},

5. 生成随机字符串

function randomStr (len) {
  len = len || 32;
  var chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
  var maxPos = chars.length;
  var pwd = '';
  for (let i = 0; i < len; i++) {
    pwd += chars.charAt(Math.floor(Math.random() * maxPos));
  }
  return pwd;
};

6. 判断对象是否为空

function isEmptyObject (obj) {
    var name;
    for (name in obj) {
        return false;
    }

    return true;
},

7. 判断是否有该class

export function hasClass(el, className){
    let reg = new RegExp('(^|\\S)'+className+'(\\s|$)');
    return reg.test(el.className);
}

8. 改dom增加class

export function addClass(el, className){

    if(hasClass(el, className)){
        return;
    }

    let newClass=el.className.split(' ');
    newClass.push(className);
    el.className=newClass.join(' ');
}

9. 生成随机整数

function getRandomInt(min, max) {

    return Math.floor(Math.random() * (max - min + 1) + min);

}

10. 打乱数组顺序， 洗牌算法

function shuffle(arr) {

    let _arr = arr.slice();        //深拷贝数组
    for (let i = 0; i<_arr.length; i++) {
        let j = getRandomInt(0, i);
        let t = _arr[i];
        _arr[i] = _arr[j];
        _arr[j] = t;
    }

    return _arr;

}

11. 判断是否为纯粹的对象，由 new Object 或者 {} 创建的

    function isPlainObject ( obj ) {
        var proto, Ctor;
        var toString = Object.prototype.toString;
        var getProto = Object.getPrototypeOf;  // 不是挂在原型上的
        var hasOwn = Object.prototype.hasOwnProperty;
        var fnToString = hasOwn.toString;
        var ObjectFunctionString = fnToString.call(Object);
        
        if ( !obj || toString.call( obj ) !== "[object Object]" ) {
            return false;
        }

        proto = getProto( obj );
        
        // 没有原型对象的对象 (`Object.create( null )`)
        if ( !proto ) {
            return true;
        }
        
        // 通过 new Object 出来的对象
        Ctor = hasOwn.call( proto, "constructor" ) && proto.constructor;
        return typeof Ctor === "function" && fnToString.call( Ctor ) === ObjectFunctionString;
    }

12. 移动端多次点击事件

var times = 0; // 记录点击次数
var timer;
const CLICK_TIME = 5；  // 比如连续点击5此就触发
document.body.onclick = function () {
    if (timer) {
        clearTimeout(timer);
        timer = null;
    }
    if (times >= CLICK_TIME) {
        // do something
    }
    times++;
   timer = setTimeout(function () {
        times = 0;
   }, 200)
}

---

const REWARD_TICKET = 100
function getRandomArray(count) {
  let arr = [];
  let remainTicket = 0;
  for (let i = 1; i < count; i++) {
    if (i === 1) {
      remainTicket = REWARD_TICKET;
    } else {
      remainTicket = REWARD_TICKET - arr.reduce((prev, curr) => {
        return prev + curr;
      });
    }
    if (remainTicket < 11) {
      arr.push(remainTicket);
      break;
    }
    const randomNumber = parseInt(Math.random() * remainTicket, 10);
    arr.push(randomNumber > 10 ? randomNumber : 10);
  }

  // make sure every number >= 10
  if (arr[arr.length - 1] < 10) {
    const cut = arr.splice(arr.length - 2, 2);
    arr.push(cut[0] + cut[1]);
  }
  return arr;
}