构建自己的PHP框架--抽象Controller的基类
上一篇博客中，我们将简单的路由解析和执行，从入口文件public/index.php中移入到框架中。入口文件顿时变得清爽无比～～
但是，去我们的controller里看一下，会看到如下的code：
<span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> actionView() { </span><span style="color: #800080;">$body</span> = 'Test body information'<span style="color: #000000;">; </span><span style="color: #0000ff;">require</span> '../views/site/view.php'<span style="color: #000000;">; }</span>难道我们每写一个要去渲染页面的action，都要去找相应路径的view，然后把它require进来。肯定不能这样，所以我们要抽象出一个Controller的基类，实现一个渲染页面的方法，让其他的controller继承，就可以使用相应的方法。
不用说，这个controller的基类肯定要写到框架里。而且也要写两个，一个放在base中，一个放在web中，web中的Controller继承base中的。
先来看在base中的
<span style="color: #000000;">phpnamespace sf\base;</span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Controller is the base class for classes containing controller logic. * @author Harry Sun </span><span style="color: #008000;">*/</span><span style="color: #0000ff;">class</span><span style="color: #000000;"> Controller{}</span>只有一个空类，等待添加内容。
再来看web中的
<span style="color: #000000;">phpnamespace sf\web;</span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Controller is the base class for classes containing controller logic. * @author Harry Sun </span><span style="color: #008000;">*/</span><span style="color: #0000ff;">class</span> Controller <span style="color: #0000ff;">extends</span><span style="color: #000000;"> \sf\base\Controller{ </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Renders a view * @param string $view the view name. * @param array $params the parameters (name-value pairs) that should be made available in the view. </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> render(<span style="color: #800080;">$view</span>, <span style="color: #800080;">$params</span> =<span style="color: #000000;"> []) { </span><span style="color: #008080;">extract</span>(<span style="color: #800080;">$params</span><span style="color: #000000;">); </span><span style="color: #0000ff;">return</span> <span style="color: #0000ff;">require</span> '../views/' . <span style="color: #800080;">$view</span> . '.php'<span style="color: #000000;">; }}</span>可以看到，我们首先从数组中把变量导入到当前的符号表中，然后引入相应的view页面。
然后，在SiteController，我们只需要这么写就可以了。
<span style="color: #000000;">phpnamespace app\controllers;</span><span style="color: #0000ff;">use</span><span style="color: #000000;"> sf\web\Controller;</span><span style="color: #0000ff;">class</span> SiteController <span style="color: #0000ff;">extends</span><span style="color: #000000;"> Controller{ </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> actionTest() { </span><span style="color: #0000ff;">echo</span> 'success!'<span style="color: #000000;">; } </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> actionView() { </span><span style="color: #800080;">$this</span>->render('site/view', ['body' => 'Test body information'<span style="color: #000000;">]); }}</span>然后，访问http://localhost/simple-framework/public/index.php?r=site/view，就可以看到跟之前一样的页面了。
我们来完善一下base中的Controller
<span style="color: #000000;">phpnamespace sf\base;</span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Controller is the base class for classes containing controller logic. * @author Harry Sun </span><span style="color: #008000;">*/</span><span style="color: #0000ff;">class</span><span style="color: #000000;"> Controller{ </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * @var string the ID of this controller. </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #800080;">$id</span><span style="color: #000000;">; </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * @var Action the action that is currently being executed. </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #800080;">$action</span><span style="color: #000000;">;}</span>添加了两个属性，分别来记录当前的controller和action。
然后，我们要在解析router之后，将其赋值，code如下：
<span style="color: #000000;">phpnamespace sf\web;</span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Application is the base class for all application classes. * @author Harry Sun </span><span style="color: #008000;">*/</span><span style="color: #0000ff;">class</span> Application <span style="color: #0000ff;">extends</span><span style="color: #000000;"> \sf\base\Application{ </span><span style="color: #008000;">/*</span><span style="color: #008000;">* * Handles the specified request. * @return Response the resulting response </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> handleRequest() { </span><span style="color: #800080;">$router</span> = <span style="color: #800080;">$_GET</span>['r'<span style="color: #000000;">]; </span><span style="color: #0000ff;">list</span>(<span style="color: #800080;">$controllerName</span>, <span style="color: #800080;">$actionName</span>) = <span style="color: #008080;">explode</span>('/', <span style="color: #800080;">$router</span><span style="color: #000000;">); </span><span style="color: #800080;">$ucController</span> = <span style="color: #008080;">ucfirst</span>(<span style="color: #800080;">$controllerName</span><span style="color: #000000;">); </span><span style="color: #800080;">$controllerNameAll</span> = <span style="color: #800080;">$this</span>->controllerNamespace . '\\' . <span style="color: #800080;">$ucController</span> . 'Controller'<span style="color: #000000;">; </span><span style="color: #800080;">$controller</span> = <span style="color: #0000ff;">new</span> <span style="color: #800080;">$controllerNameAll</span><span style="color: #000000;">(); </span><span style="color: #800080;">$controller</span>->id = <span style="color: #800080;">$controllerName</span><span style="color: #000000;">; </span><span style="color: #800080;">$controller</span>->action = <span style="color: #800080;">$actionName</span><span style="color: #000000;">; </span><span style="color: #0000ff;">return</span> <span style="color: #008080;">call_user_func</span>([<span style="color: #800080;">$controller</span>, 'action'. <span style="color: #008080;">ucfirst</span>(<span style="color: #800080;">$actionName</span><span style="color: #000000;">)]); }}</span>然后我们就可以在controller和view中拿到相应的controller名字和action名字了，将view.php修改如下：
<span style="color: #0000ff;"><span style="color: #800000;">html</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">head</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>title<span style="color: #0000ff;"></span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">head</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">body</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"></span><span style="color: #ff00ff;">php echo $this->id;</span><span style="color: #0000ff;">?></span><span style="color: #0000ff;"><span style="color: #800000;">br</span><span style="color: #0000ff;">/></span> <span style="color: #0000ff;"></span><span style="color: #ff00ff;">php echo $this->action;</span><span style="color: #0000ff;">?></span><span style="color: #0000ff;"><span style="color: #800000;">br</span><span style="color: #0000ff;">/></span> <span style="color: #0000ff;"></span><span style="color: #ff00ff;">php echo $body;</span><span style="color: #0000ff;">?></span> <span style="color: #0000ff;"></span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span><span style="color: #0000ff;"></span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span></span></span></span></span></span></span></span>
然后我们就可以看到如下的页面了
有人觉得现在大家都前后端分离了，我们不需要用PHP去render一个页面，只需要返回一个josn字符串就好了，这个就更简单了，在web的Controller中添加一个toJson方法即可
<span style="color: #008000;">/*</span><span style="color: #008000;">* * Convert a array to json string * @param string $data </span><span style="color: #008000;">*/</span> <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> toJson(<span style="color: #800080;">$data</span><span style="color: #000000;">) { </span><span style="color: #0000ff;">if</span> (<span style="color: #008080;">is_string</span>(<span style="color: #800080;">$data</span><span style="color: #000000;">)) { </span><span style="color: #0000ff;">return</span> <span style="color: #800080;">$data</span><span style="color: #000000;">; } </span><span style="color: #0000ff;">return</span> json_encode(<span style="color: #800080;">$data</span><span style="color: #000000;">); }</span>将SiteController中的actionTest，修改如下：
<span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> actionTest() { </span><span style="color: #800080;">$data</span> = ['first' => 'awesome-php-zh_CN', 'second' => 'simple-framework'<span style="color: #000000;">]; </span><span style="color: #0000ff;">echo</span> <span style="color: #800080;">$this</span>->toJson(<span style="color: #800080;">$data</span><span style="color: #000000;">); }</span>访问http://localhost/simple-framework/public/index.php?r=site/view，你就可以看到相应的json字符串了。
好了，今天就先到这里。项目内容和博客内容也都会放到Github上，欢迎大家提建议。
code：https://github.com/CraryPrimitiveMan/simple-framework/tree/0.3
blog project：https://github.com/CraryPrimitiveMan/create-your-own-php-framework
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