Symfony之components--第二章--第二讲：BrowserKit组件的使用

BrowserKit Component
simulates(模拟)一个网络浏览器的习惯，允许你发送请求，点击链接和表单提交．
Basic Usage
创建一个客户
该组建只提供哦你一个抽象的客户段，并且不提供任何后台http层的任何操作．
创建自己的client，你必须继承一个抽象的Client类并且实现doRequest()方法．
这个方法接受一个请求并且应该返回一个响应．
namespace Acme;


use Symfony\Component\BrowserKit\Client as BaseClient;
use Symfony\Component\BrowserKit\Response;


class Client extends BaseClient
{
    protected function doRequest($request)
    {
        // ... convert request into a response


        return new Response($content, $status, $headers);
    }
}


发送请求
用request()方法去发送一个http请求．前两个参数是http方法和请求的url：
use Acme\Client;


$client = new Client();
$crawler = $client->request('GET', 'http://symfony.com');
共过request()方法返回的值是Crawler类的一个实例，允许以编程的方式访问和遍历html元素．


Clicking Links
Crawler对象可以模拟链接点击．首先，通过给selectLink()方法设置链接的文本内容，返回一个Link对象．
然后通过给click方法设置这个Link对象，执行需要的http get请求，从而模拟链接点击．
use Acme\Client;


$client = new Client();
$crawler = $client->request('GET', 'http://symfony.com');
$link = $crawler->selectLink('Go elsewhere...')->link();
$client->click($link);


Submitting Forms
Crawler对象之能够选择表单．首相，通过selectButton()方法选择任何一个表单按钮．
然后，通过form()方法去选择这个按钮所属表单．
在选择了表单之后，填写他的数据并且通过submit()方法提交它．
use Acme\Client;


// make a real request to an external site
$client = new Client();
$crawler = $client->request('GET', 'https://github.com/login');


// select the form and fill in some values
$form = $crawler->selectButton('Log in')->form();
$form['login'] = 'symfonyfan';
$form['password'] = 'anypass';


// submit that form
$crawler = $client->submit($form);


Cookies
retrieving(检索)　cookies
Client通过一个CookieJar实现了暴露的cookies，允许你去存储和检索任何cookie当你在客户端
发送请求的时候．
use Acme\Client;


// Make a request
$client = new Client();
$crawler = $client->request('GET', 'http://symfony.com');


// Get the cookie Jar
$cookieJar = $client->getCookieJar();


// Get a cookie by name
$cookie = $cookieJar->get('name_of_the_cookie');


// Get cookie data
$name       = $cookie->getName();
$value      = $cookie->getValue();
$raw        = $cookie->getRawValue();
$secure     = $cookie->isSecure();
$isHttpOnly = $cookie->isHttpOnly();
$isExpired  = $cookie->isExpired();
$expires    = $cookie->getExpiresTime();
$path       = $cookie->getPath();
$domain     = $cookie->getDomain();


Looping Through Cookies
use Acme\Client;


// Make a request
$client = new Client();
$crawler = $client->request('GET', 'http://symfony.com');


// Get the cookie Jar
$cookieJar = $client->getCookieJar();


// Get array with all cookies
$cookies = $cookieJar->all();
foreach ($cookies as $cookie) {
    // ...
}


// Get all values
$values = $cookieJar->allValues('http://symfony.com');
foreach ($values as $value) {
    // ...
}


// Get all raw values
$rawValues = $cookieJar->allRawValues('http://symfony.com');
foreach ($rawValues as $rawValue) {
    // ...
}


Setting Cookies
你可以之创建cookies并且添加他们到cookiejar，可以注入到客户端的构造函数：
use Acme\Client;


// create cookies and add to cookie jar
$cookieJar = new Cookie('flavor', 'chocolate', strtotime('+1 day'));


// create a client and set the cookies
$client = new Client(array(), array(), $cookieJar);
// ...


History
客户端存储所有你的请求，允许在你的历史浏览记录中返回或者前进
use Acme\Client;


// make a real request to an external site
$client = new Client();
$client->request('GET', 'http://symfony.com');


// select and click on a link
$link = $crawler->selectLink('Documentation')->link();
$client->click($link);


// go back to home page
$crawler = $client->back();


// go forward to documentation page
$crawler = $client->forward();
你可以删除客户端的历史，通过restart()方法．这也将删除所有的cookies:
use Acme\Client;


// make a real request to an external site
$client = new Client();
$client->request('GET', 'http://symfony.com');


// delete history
$client->restart();