原生JS数组方法重构：sort、reverse、push、pop等

1.sort

       Array.prototype.mySort=function(){
             for(var i=0;i<arr.length;i++){
                           var min = i;
                            for(var j=i+1;j<arr.length;j++){
                              if(arr[j]<arr[min]){
                                    min = j
                             }
                            }
                             var temp = arr[i]
                                 arr[i] = arr[min]
                                 arr[min] = temp
                         }  
                           return arr;
             }

2.reverse

Array.prototype.myReverse = function(){
        for(var i = 0;i<this.length/2;i++){
            var temp = this[i];
            this[i] = this[this.length-1-i];
            this[this.length-1-i] = temp;
        }
        return this;
    }

3.push

Array.prototype.myPush = function(){
            var len = this.length;
            for(var key in arguments){
                this[(len+(+key))] = arguments[key];
            }
            return this.length;
        }

4.pop

Array.prototype.myPop = function(){
            var result = this[this.length-1];
            this.length--;
            return result
        }

5.shift

Array.prototype.myShift = function(){
            var result = this[0];
            for(i=0;i<this.length-1;i++){
                this[i] = this[i+1];
            }
            this.length--;
            return result;
        }

6.unshift

Array.prototype.myUnshift = function(){
            for(var i = this.length-1;i>=0;i--){
                this[i+arguments.length] = this[i];
            }
            for(var j = arguments.length-1;j>=0;j--){
                this[j] = arguments[j]
            }
            return this.length
        }

7.slice

Array.prototype.mySlice = function(a,b){
            var new_arr = JSON.parse(JSON.stringify(this));
            var temp = [];
            for(var i = a;i<b;i++){
                temp[temp.length] = new_arr[i];
            }
            return temp;
        }