对象的浅拷贝与深拷贝

浅拷贝

var a = {
  name : '小明'
};

var b = {};

extend(b,a)

function extend(obj1,obj2) {
  for(var attr in obj2) {
    obj1[attr] = obj2[attr];
  }
}

深拷贝

function deepCopy(obj){  //深拷贝
    var newObj = {};

    if(typeof obj != 'object'){
        //console.trace();
        return obj;
    }
    
    for(var attr in obj){  

        newObj[attr] = deepCopy(obj[attr]); 
    }
    //console.trace();
    //console.log(newObj);
    return newObj;

    
}