前面的话
前面的博文中介绍了对象拷贝，本文将详细介绍数组复制
push
var obj1=[1,2,3];
var obj2=copyArray(obj1);
console.log(obj1); //[1,3]
console.log(obj2); //[1,3]
obj2.push(4);
console.log(obj1); //[1,3,4]
var obj2=copyArray(obj1);
console.log(obj1); //[1,3]
console.log(obj2); //[1,3]
obj2.push(4);
console.log(obj1); //[1,3,4]
join 使用该方法的缺点是数组中的项全部变成了字符串形式
var obj1=[1,3]
console.log(obj2); //['1','2','3']
obj2.push(4);
console.log(obj1); //[1,'3',4]
console.log(obj2); //['1','2','3']
obj2.push(4);
console.log(obj1); //[1,'3',4]
concat
var obj1=[1,4]
slice
var obj1=[1,4]
深拷贝
以上方法实现的仅是数组的浅拷贝，如果要实现数组的深拷贝，需要使用递归方法
var obj1=[1,[3,4]];
var obj2=copyArray(obj1);
console.log(obj1[2]); //[3,4]
console.log(obj2[2]); //[3,4]
obj2[2].push(5);
console.log(obj1[2]); //[3,4,5]
var obj2=copyArray(obj1);
console.log(obj1[2]); //[3,4]
console.log(obj2[2]); //[3,4]
obj2[2].push(5);
console.log(obj1[2]); //[3,4,5]
