HTTP Requests|Lumen 中文文档

Obtaining A Request Instance
Via Facade
The Request facade will grant you access to the current request that is bound in the container. For example:
```
$name = Request::input('name');
```
Remember, if you are in a namespace, you will have to import the Request facade using a use Request; statement at the top of your class file.

Via Dependency Injection
To obtain an instance of the current HTTP request via dependency injection, you should type-hint the class on your controller constructor or method. The current request instance will automatically be injected by the service container:
```
<?php namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;

class UserController extends Controller {

/**
	 * Store a new user.
	 *
	 * @param  Request  $request
	 * @return Response
	 */
	public function store(Request $request)
	{
		$name = $request->input('name');

//
	}

}
```
If your controller method is also expecting input from a route parameter, simply list your route arguments after your other dependencies:
```
<?php namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;

class UserController extends Controller {

/**
	 * Store a new user.
	 *
	 * @param  Request  $request
	 * @param  int  $id
	 * @return Response
	 */
	public function update(Request $request, $id)
	{
		//
	}

}
```
Retrieving Input
Retrieving An Input Value
Using a few simple methods, you may access all user input from your Illuminate\Http\Request instance. You do not need to worry about the HTTP verb used for the request, as input is accessed in the same way for all verbs.
```
$name = Request::input('name');
```
Retrieving A Default Value If The Input Value Is Absent
```
$name = Request::input('name', 'Sally');
```
Determining If An Input Value Is Present
```
if (Request::has('name')) {
	//
}
```
Getting All Input For The Request
```
$input = Request::all();
```
Getting Only Some Of The Request Input
```
$input = Request::only('username', 'password');

$input = Request::except('credit_card');
```
When working on forms with "array" inputs, you may use dot notation to access the arrays:
```
$input = Request::input('products.0.name');
```
Old Input
Note: Before utilizing this feature of Lumen, you must enable sessions.

Lumen, like Laravel, also allows you to keep input from one request during the next request. For example, you may need to re-populate a form after checking it for validation errors.

Flashing Input To The Session
The flash method will flash the current input to the session so that it is available during the user's next request to the application:
```
Request::flash();
```
Flashing Only Some Input To The Session
```
Request::flashOnly('username', 'email');

Request::flashExcept('password');
```
Flash & Redirect
Since you often will want to flash input in association with a redirect to the previous page, you may easily chain input flashing onto a redirect.
```
return redirect('form')->withInput();

return redirect('form')->withInput(Request::except('password'));
```
Retrieving Old Data
To retrieve flashed input from the previous request, use the old method on the Request instance.
```
$username = Request::old('username');
```
If you are displaying old input within a Blade template, it is more convenient to use the old helper:
```
{{ old('username') }}
```
Cookies
To force all cookies to be encrypted and signed, you will need to uncomment the EncryptCookies middleware in your bootstrap/app.php file. All signed cookies created by the Lumen and Laravel frameworks are encrypted and signed with an authentication code, meaning they will be considered invalid if they have been changed by the client.

Retrieving A Cookie Value
```
$value = Request::cookie('name');
```
Attaching A New Cookie To A Response
The cookie helper serves as a simple factory for generating new Symfony\Component\HttpFoundation\Cookie instances. The cookies may be attached to a Response instance using the withCookie method:
```
$response = new Illuminate\Http\Response('Hello World');

$response->withCookie(cookie('name', 'value', $minutes));
```
Creating A Cookie That Lasts Forever*
By "forever", we really mean five years.
```
$response->withCookie(cookie()->forever('name', 'value'));
```
Queueing Cookies
Note: In order to utilize this feature of Lumen, you must uncomment the AddQueuedCookiesToResponse middleware in your bootstrap/app.php file.

You may also "queue" a cookie to be added to the outgoing response, even before that response has been created:
```
<?php namespace App\Http\Controllers;

use Cookie;
use App\Http\Controllers\Controller;

class UserController extends Controller
{
	/**
	 * Update a resource
	 *
	 * @return Response
	 */
	 public function update()
	 {
	 	Cookie::queue('name', 'value');

return response('Hello World');
	 }
}
```
Files
Retrieving An Uploaded File
```
$file = Request::file('photo');
Determining If A File Was Uploaded
if (Request::hasFile('photo')) {
	//
}
```
The object returned by the file method is an instance of the Symfony\Component\HttpFoundation\File\UploadedFile class, which extends the PHP SplFileInfo class and provides a variety of methods for interacting with the file.

Determining If An Uploaded File Is Valid
```
if (Request::file('photo')->isValid()) {
	//
}
```
Moving An Uploaded File
```
Request::file('photo')->move($destinationPath);

Request::file('photo')->move($destinationPath, $fileName);
```
Other File Methods
There are a variety of other methods available on UploadedFile instances. Check out the API documentation for the class for more information regarding these methods.

Other Request Information
The Request class provides many methods for examining the HTTP request for your application and extends the Symfony\Component\HttpFoundation\Request class. Here are some of the highlights.

Retrieving The Request URI
```
$uri = Request::path();
```
Retrieving The Request Method
```
$method = Request::method();

if (Request::isMethod('post')) {
	//
}
```
Determining If The Request Path Matches A Pattern
```
if (Request::is('admin/*')) {
	//
}
```
Get The Current Request URL
```
$url = Request::url();
```