Tutorial（二）

    For this tutorial, we'll use prebuilt JavaScript files on a CDN. Open up your favorite editor and create a new HTML document:

    For the remainder of this tutorial, we'll be writing our JavaScript code in this script tag.

    Note:
    We included jQuery here because we want to simplify the code of our future ajax calls, but it's NOT mandatory for React to work.

    Your first component
    React is all about modular, composable components. For our comment box example, we'll have the following component structure:

    - CommentBox
      - CommentList
        - Comment
      - CommentForm

:
让我们来建立一个评论组件，一个简单的 div 标签

    Note that native HTML element names start with a lowercase letter, while custom React classes names begin with an uppercase letter.

说明了native 的 HTML 结点，命名都是以一个小写字母开始，但客户端的React 类命名以大写字母开始。

    The first thing you'll notice is the XML-ish syntax in your JavaScript. We have a simple precompiler that translates the syntactic sugar to this plain JavaScript:

你注意到的第一件是是 XML-ish 语法在你的javascript 代码中，有一个简单的程序，将这一纯JavaScript语法糖转化为原码的javascript：

    Its use is optional but we've found JSX syntax easier to use than plain JavaScript。

它的使用是可选的，但我们发现JSX语法比纯JavaScript更容易使用

    We pass some methods in a JavaScript object to React.createClass() to create a new React component.

我们通过一些方法，在react中使用createclass()创建一个新的 React 元件。

    The most important of these methods is called render which returns a tree of React components that will eventually render to HTML.

这些方法中最重要的是 reader ，返回一个react 组件树（最总会转化为 HTML）。

    The <div> tags are not actual DOM nodes; they are instantiations of React div components. 

这些div 标签不是真实的结点，他们是 react 组件的实例。

    You can think of these as markers or pieces of data that React knows how to handle.

你可以把这些作为标志或数据块，React知道如何处理。

    React is safe. We are not generating HTML strings so XSS protection is the default.

react 是安全的。我们不是生成的HTML字符串，XSS保护是默认的。

    You do not have to return basic HTML. You can return a tree of components that you (or someone else) built. This is what makes React composable: a key tenet of maintainable frontends.

你不必返回基本的HTML。你可以返回一个，你（或其他人）建的组件树。
这就是什么使得React的可组合：可维护的前端的关键原则。

    React.render() instantiates the root component, starts the framework, and injects the markup into a raw DOM element, provided as the second argument.

react.render（），实例化根组件，启动框架，并将标记为原始DOM元素，作为第二个参数。