Get URL parameters inside custom module

I've created a custom block like this:

class HelloBlock extends BlockBase implements BlockPluginInterface{

/**
* {@inheritdoc}
*/
public function build() {
$config = $this->getConfiguration();
$result = db_query('SELECT * FROM {test}');
return array(
'#theme' => 'world',
'#test' => $result
);
}
}

And I now want to programmatically get some parameter from the URL.

For example:

If the URL is `http://localhost/drup/hello/5569` I want to get hold of the value `5569` inside my module.

I have tried `arg(1)` and `drupal_get_query_parameters()` but I got this error messages:

Call to undefined function `Drupal\hello\Plugin\Block\arg()`

and

Call to undefined function `Drupal\hello\Plugin\Block\drupal_get_query_parameters()`

How can I get the parameters?

$route_match = \Drupal::service('current_route_match');
$abc = $route_match->getParameter('node'); //node is refrence to what you have written in you routing file i.e:

in something.routing.yml
entity.node.somepath:
path: '/some/{node}/path'


I have used {node} as arg(1). And I can access it by using *->getParameter('node');

Hope this will work.

I used to get the parameter value from URL (localhost/check/myform?mob=89886665)

$param = \Drupal::request()->query->all();

And applied in my select Query

$query = \Drupal::database()->select('profile_register', 'p1');
$query->fields('p1');
$query->condition('p1.mobileno', $edituseprof);
$query->condition('publishstatus', 'no');
$result = $query->execute()->fetchAll();

But on multiple parameter value, i am now successful(**Ex:**

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)

$query = \Drupal::database()->select('profile_register', 'p1');
$query->fields('p1');
$query->condition('p1.mobileno', $edituseprof['mob']);
$query->condition('p1.ids', $edituseprof['id']);
$query->condition('publishstatus', 'no');
$result = $query->execute()->fetchAll();

The Drupal docs are great on this:

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1. define your path variable in yaml

example.name:
path: '/example/{name}'
...

2. Add the variable in your method and use it

<?php
class ExampleController {
// ...
public function content($name) {
// Name is a string value.
// Do something with $name.
}
}
?>

arg() is deprecated in drupal 8, however we can get values like arg() function does in drupal 7 & 6

$path = \Drupal::request()->getpathInfo();
$arg = explode('/',$path);
print_r($arg); exit();

The output would be parameters in url except basepath or (baseurl),

Array
(
[0] =>
[1] => node
[2] => add
)

To get query parameter form the url, you can us the following.
If you have the url for example,

domainname.com/page?uid=123&num=452

To get **"uid"** from the url, use..

$uid = \Drupal::request()->query->get('uid');

To get **"num"** from the url, use..

$num = \Drupal::request()->query->get('num');

If your url is like this below example

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Then you have to get the full url path by

$current_path = \Drupal::request()->getPathInfo();

then explode the path to get the arguments array.

$path_args = explode('/', $current_path);

Another example if value passed by a key in url like below where id contains the value

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You can get the id by given drupal request

$id = \Drupal::request()->query->get('id');

Use `\Drupal\Core\Routing;`:

$parameters = \Drupal::routeMatch()->getParameters();

The named parameters are available as

$value = \Drupal::routeMatch()->getParameter('slug_name_from_route');

Where 'slug_name_from_router' comes from your routing.yml path property

path: '/your/path/{slug_name_from_route}'

If you want the raw parameter without any [upcasting](

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) you can get

$value = \Drupal::routeMatch()->getRawParameter('slug_name_from_route');

Here's the example of accessing URL parameters and passing them to a TWIG template,
I am considering you have already created your module and required files and suppose "/test?fn=admin" is your URL

1. In Your .module file implement hook_theme and define variables and template name (Make sure you replace "_" with "-" when creating the template file)

function my_module_theme () {
return [
'your_template_name' => [
'variables' => [
'first_name' => NULL,
],
];
}

Now create your controller and put below code in it.

namespace Drupal\my_module\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\Request;


class MyModule extends ControllerBase {

public function content(Request $request) {

return [
'#theme' => 'my_template',
'#first_name' => $request->query->get('fn'), //This is because the parameters are in $_GET, if you are accessing from $_POST then use "request" instead "query"
];
}

}

Now in your TWIG file which should be "my-template.html.twig" you can access this parameter as,

<h3>First Name: {{ first_name }}</h3>

And its done.
Hope this helps.