深度克隆

1.遍历对象 for(var prop in obj)
2.判断是不是原始值 typeof()
3.判断是数组还是对象 instanceof toString constructor
4.建立相应的数组或对象
5.递归

var obj = {
    name : "abc",
    age : 123,
    card : ['visa','master'],
    wife : {
        name : "bcd",
        son : {
            name : "aaa"
        }
    }
}

function deepClone(origin,target){
    var target = target || {},
        toStr = Object.prototype.toString,
        arrStr = "[object Array]";
    for(var prop in origin){//遍历对象
        if(origin.hasOwnProperty(prop)){//判断是不是原型链上的
            if(origin[prop] !== "null" && typeof(origin[prop]) == 'object'){//判断是不是原始值
                if(toStr.call(origin[prop]) == arrStr){//判断是对象还是数组
                    target[prop] = [];

                }else{
                    target[prop] = {};
                }
                deepClone(origin[prop],target[prop]);//递归

            }else{
                target[prop] = origin[prop];//原始值
            }
        }
    }
    return target
}