js深入研究之克隆，属性，数组，对象，函数

代码

<script type="text/javascript">
/* 克隆原型得到对象 */
function clone(object) {
    function F() {}
    F.prototype = object;
    return new F;
}

var Person = {
  name: 'default name',
  getName: function() {
    return this.name;
  }
};

var reader = clone(Person);
console.log(reader.getName()); // This will output 'default name'.
reader.name = 'John Smith';
console.log(reader.getName()); // This will now output 'John Smith'.

/* Author Prototype Object. */

var Author = clone(Person);
Author.books = []; // 书数组
Author.getBooks = function() {
  return this.books;
}

var author = [];

author[0] = clone(Author);
author[0].name = 'Dustin Diaz';
author[0].books = ['JavaScript Design Patterns'];

author[1] = clone(Author);
author[1].name = 'Ross Harmes';
author[1].books = ['JavaScript Design Patterns','PHP','Mysql'];
console.log(author[0].getName());
console.log(author[0].getBooks());
console.log(author[1].getName());
console.log(author[1].getBooks());
</script>

结果

这里的console.log很有意思，比alert有意思，alert不能获取全部数据，需要一个个弹出。

js的数组定义也很有意思。

进一步升级

<script type="text/javascript">
/* 克隆原型得到对象 */
function clone(object) {
    function F() {}
    F.prototype = object;
    return new F;
}

var Person = {
  name: 'default name',
  getName: function() {
    return this.name;
  }
};


var Author = clone(Person);
Author.books = []; // 书数组
Author.getBooks = function() {
  return this.books;
}


var authorClone = clone(Author);
console.log(authorClone.name); // string 'default name'.
authorClone.name = 'new name'; // 重新赋值
console.log(authorClone.name); // Now linked to the primative authorClone.name, which 
                         // is the string 'new name'.
console.log(Author.getName());  // 没有改变，任然是 'default name'
console.log(Author.getBooks()); // 空的
authorClone.books.push('new book'); // Author被改了
authorClone.books.push('new new book'); // Author被改了
console.log(Author.getBooks()); // array 'new book'
console.log(authorClone.getBooks()); // array 'new book'
authorClone.books = []; // 定义了属于自己的books数组
authorClone.books.push('new book2'); // We are now modifying that new array.
authorClone.books.push('new book3');
authorClone.books.push('new book4');
console.log(authorClone.getBooks());
console.log(Author.getBooks());

var CompoundObject = {
  string1: 'default value',
  childObject: {
    bool: true,
    num: 10
  },
  getChild: function() {  // 返回对象Object
    return this.childObject;
  }
}

var compoundObjectClone = clone(CompoundObject);

compoundObjectClone.childObject.num = 5; // 不好的方式

compoundObjectClone.childObject = { // 好一点的方式
  bool: true,
  num: 5
};
console.log(compoundObjectClone.getChild());

</script>