JS数组方法reverse()用法实例分析

var arr1 = [1, 2, 3, 4, 5, 6];
var arr2 = ['A', 'B', 'C'];
var arr3 = ['AAA', 'BBB', 'CCC'];
var arr4 = ['Hello', 'World'];
Array.prototype.copyReverse =function() { 
  var result = [],
    len = this.length;
    for(var i = 0; i < len; i++) {
      result[result.length] = this[len - i - 1];
    }
    for(var i = 0; i < result.length; i++) {
      this[i] = result[i];
    }
  return this;
};
console.log(arr1.copyReverse()); // [6, 5, 4, 3, 2, 1]
console.log(arr2.copyReverse()); // ["C", "B", "A"]
console.log(arr3.copyReverse()); // ["CCC", "BBB", "AAA"]
console.log(arr4.copyReverse()); // ["World", "Hello"]