PHP 闭包详解及实例代码

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<?php
$clousre = function ($name) {
return 'Hello ' . $name;
};
echo $closure('nesfo');

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<?php
$numbersPlusOne = array_map(function ($number) {
return $number + 1;
}, [1, 2, 3]);
print_r($numbersPlusOne);

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[2, 3, 4]

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<?php
function incrementNum ($number) {
return $number + 1;
}
$numbersPlusOne = array_map('incrementNum', [1, 2, 3]);
print_r($numbersPlusOne);

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<?php
function enclosePerson ($name) {
return function ($doCommand) use ($name) {
return $name . ', ' . $doCommand;
}
}
$clay = enclosePerson('Clay');
echo $clay('get me sweet tea!');

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"Clay, get me sweet tea!"

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<?php
class App
{
protected $routes = [];
protected $responseStatus = '200 OK';
protected $responseContentType = 'text/html';
protected $responseBody = 'Hello world';
public function addRoute($routePath, $routeCallback){
$this->routes[$routePath] = $routeCallback->bindTo($this, __CLASS__);
}
public function dispatch($currentPath){
foreach($this->routes as $routePath => $callback){
if ($routePath === $currentPath) {
$callback();
}
}
header('HTTP/1.1' . $this->responseStatus);
header('Content-type: ' . $this->responseContentType);
header('Content-length' . mb_strlen($this->responseBody));
echo $this->responseBody;
}
}

<?php
$app = new App();
$app->addRoute('/user/nesfo', function () {
$this->responseContentType = 'application/json; charset=utf8';
$this->responseBody = '{"name": "nesfo"}';
});
$app->dispatch('/user/nesfo');

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