[ Laravel 5.2 文档 ] 基础 -- 视图
1、基本使用
视图包含应用的 HTML 代码并将应用的控制器逻辑和表现逻辑进行分离。视图文件存放在 resources/views目录。
下面是一个简单视图:
<!-- 该视图存放 resources/views/greeting.php --><html> <body> <h1 id="Hello-php-echo-name">Hello, <?php echo $name; ?></h1> </body></html>
由于这个视图存放在 resources/views/greeting.php,我们可以在全局的辅助函数 view中这样返回它:
Route::get('/', function () { return view('greeting', ['name' => 'James']);});
正如你所看到的,传递给 view方法的第一个参数是 resources/views目录下相应的视图文件的名字,第二个参数是一个数组,该数组包含了在该视图中所有有效的数据。在这个例子中,我们传递了一个 name变量,在视图中通过执行 echo将其显示出来。
当然,视图还可以嵌套在 resources/views的子目录中,用“.”号来引用嵌套视图,比如,如果视图存放路径是 resources/views/admin/profile.php,那我们可以这样引用它:
return view('admin.profile', $data);
判断视图是否存在
如果需要判断视图是否存在,可调用在不带参数的 view之后使用 exists方法,如果视图在磁盘存在则返回 true:
if (view()->exists('emails.customer')) { //}
调用不带参数的 view时,将会返回一个 Illuminate\Contracts\View\Factory实例,从而可以调用该工厂上的所有方法。
2、视图数据
传递数据到视图
在上述例子中可以看到,我们可以简单通过数组方式将数据传递到视图:
return view('greetings', ['name' => 'Victoria']);
以这种方式传递数据的话, $data应该是一个键值对数组,在视图中,就可以使用相应的键来访问数据值,比如 。除此之外,还可以通过 with方法添加独立的数据片段到视图:
$view = view('greeting')->with('name', 'Victoria');
在视图间共享数据
有时候我们需要在所有视图之间共享数据片段,这时候可以使用视图工厂的 share方法,通常,需要在服务提供者的 boot方法中调用 share方法,你可以将其添加到 AppServiceProvider或生成独立的服务提供者来存放它们:
<?phpnamespace App\Providers;class AppServiceProvider extends ServiceProvider{ /** * 启动所有应用服务 * * @return void */ public function boot() { view()->share('key', 'value'); } /** * 注册服务提供者 * * @return void */ public function register() { // }}
3、视图Composer
视图 Composer 是当视图被渲染时的回调或类方法。如果你有一些数据要在视图每次渲染时都做绑定,可以使用视图 Composer 将逻辑组织到一个单独的地方。
首先要在服务提供者中注册视图 Composer,我们将会使用辅助函数 view来访问 Illuminate\Contracts\View\Factory的底层实现,记住,Laravel 不会包含默认的视图 Composer 目录,我们可以按照自己的喜好组织其路径,例如可以创建一个 App\Http\ViewComposers目录:
<?phpnamespace App\Providers;use Illuminate\Support\ServiceProvider;class ComposerServiceProvider extends ServiceProvider{ /** * 在容器中注册绑定. * * @return void * @author http://laravelacademy.org */ public function boot() { // 使用基于类的composers... view()->composer( 'profile', 'App\Http\ViewComposers\ProfileComposer' ); // 使用基于闭包的composers... view()->composer('dashboard', function ($view) { }); } /** * 注册服务提供者. * * @return void */ public function register() { // }}
如果创建一个新的服务提供者来包含视图 Composer 注册,需要添加该服务提供者到配置文件 config/app.php的 providers数组中。
现在我们已经注册了 Composer,每次 profile视图被渲染时都会执行 ProfileComposer@compose,接下来我们来定义该 Composer 类:
<?phpnamespace App\Http\ViewComposers;use Illuminate\Contracts\View\View;use Illuminate\Users\Repository as UserRepository;class ProfileComposer{ /** * 用户仓库实现. * * @var UserRepository */ protected $users; /** * 创建一个新的属性composer. * * @param UserRepository $users * @return void */ public function __construct(UserRepository $users) { // Dependencies automatically resolved by service container... $this->users = $users; } /** * 绑定数据到视图. * * @param View $view * @return void */ public function compose(View $view) { $view->with('count', $this->users->count()); }}
视图被渲染前,Composer 类的 compose 方法被调用,同时 Illuminate\Contracts\View\View被注入该方法,从而可以使用其 with方法来绑定数据到视图。
注意:所有视图 Composer 都通过服务容器被解析,所以你可以在 Composer 类的构造函数中声明任何你需要的依赖。
添加 Composer 到多个视图
你可以传递视图数组作为 composer方法的第一个参数来一次性将视图 Composer 添加到多个视图:
view()->composer( ['profile', 'dashboard'], 'App\Http\ViewComposers\MyViewComposer');
composer方法接受 *通配符,从而允许将一个 Composer 添加到所有视图:
view()->composer('*', function ($view) { //});
4、视图创建器
视图创建器和视图 Composer 非常类似,不同之处在于前者在视图实例化之后立即失效而不是等到视图即将渲染。使用 create方法即可注册一个视图创建器:
view()->creator('profile', 'App\Http\ViewCreators\ProfileCreator');

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics











PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

In PHP, password_hash and password_verify functions should be used to implement secure password hashing, and MD5 or SHA1 should not be used. 1) password_hash generates a hash containing salt values to enhance security. 2) Password_verify verify password and ensure security by comparing hash values. 3) MD5 and SHA1 are vulnerable and lack salt values, and are not suitable for modern password security.

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7

PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.

PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.

PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.
