How do I implement a non-fixed number of parameters in a Laravel route ?, Laravel route

How do I implement a non-fixed number of parameters in a Laravel route ?, Laravel route

Preface

Laravel is a good framework. I am also studying and using it and promoting it in my company. I recently found a particularly interesting piece of code while reading the Laravel Source Code. For details, refer:

... What are these three points used? I checked the PHP manual and found that this is a list of variable parameters.

What is this? The PHP manual explains this.

... Is a list of parameters that can be changed in user-defined functions.

... Exists in PHP 5.6 and later versions. Use functions in PHP 5.5 and earlier versions func_num_args(),func_get_arg() , Andfunc_get_args().

Variable Number Parameter List, which may be abstract.

We can understand that we have customized a function or a function, but the number of parameters of this function is not fixed, that is, the list of variable parameters.

For the variable quantity parameter list, let's look at two examples;

<?phpfunction sum(...$numbers) { $acc = 0; foreach ($numbers as $n) {  $acc += $n; } return $acc;}echo sum(1, 2, 3, 4);?>

The above routine will output:

10

The variable quantity parameter is passed to the function, and the given parameter variable is used as an array.

Let's look at another example:

<?phpfunction add($a, $b) { return $a + $b;}echo add(...[1, 2])?>

The above routine will output:

3

The variable quantity parameter is passed to the function, and the given array is used as the parameter variable.

What is the relationship between this variable quantity parameter and Laravel routing?

In Laravel, custom routing is very free, for example:

Route: get ('user/{id} ', 'userscontroller @ filter'); // public function filter ($ id) {# code ...}

It may be like this:

Route: get ('user/{id}/{name} ', 'userscontroller @ filter'); // public function filter ($ id, $ name) {# code ...}

In Laravel routing, how does one implement such a number of parameters in the code? The variable quantity parameter is used.

// */vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php/** * Dispatch a request to a given controller and method. * * @param \Illuminate\Routing\Route $route * @param mixed $controller * @param string $method * @return mixed */public function dispatch(Route $route, $controller, $method){ $parameters = $this->resolveClassMethodDependencies(  $route->parametersWithoutNulls(), $controller, $method ); if (method_exists($controller, 'callAction')) {  return $controller->callAction($method, $parameters); } return $controller->{$method}(...array_values($parameters));}

I have to admire Laravel's author Taylor naoluqing!

Summary

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