link - PHP code example

PHP Function Link - Creating a Link Between PHP and HTML

PHP Functions are a programming technique that allow you to split your code into smaller and more manageable pieces. The benefit of using functions is that they can be reused across multiple projects, making your code more scalable and easier to read.

One of the most important PHP Functions that every developer needs to know is the php function link. This function is used to create a link between PHP and HTML files. Typically, you would want to use this method when you are connecting an external PHP script to your HTML file.

The is_link() function accepts one argument – the path to the file you wish to check if it’s a symbolic link. It returns TRUE if the file exists and is a symbolic link, otherwise FALSE. It’s worth noting that the results of this function are cached, so if you need to see fresh data you can use the clearstatcache() function to refresh the stat() output.

Including a file takes all the text/code/markup that is in a file and copies it into another PHP file before running it on the server. This is a very useful tool when you need to include the same markup or scripts on multiple pages of your website.

To include a file, you simply add the include (or require) statement at the top of the file that contains the markup or code you wish to include. Then, the include file will be loaded before the other files on your site.

link example

$description_id   = '_customize-description-' . $this->id;
        $describedby_attr = ( ! empty( $this->description ) ) ? ' aria-describedby="' . esc_attr( $description_id ) . '" ' : '';
        switch ( $this->type ) {
            case 'checkbox':
                ?> <span class="customize-inside-control-row"> <input id="<?php echo esc_attr( $input_id ); ?>" <?php echo $describedby_attr; ?> type="checkbox" value="<?php echo esc_attr( $this->value() ); ?>" <?php $this->link(); ?> <?php checked( $this->value() ); ?> /> <label for="<?php echo esc_attr( $input_id ); ?>"><?php echo esc_html( $this->label ); ?></label> <?php if ( ! empty( $this->description ) ) : ?> <span id="<?php echo esc_attr( $description_id ); ?>" class="description customize-control-description"><?php echo $this->description; ?></span> <?php endif; ?> </span> <?php                 break;
            case 'radio':
                if ( empty( $this->choices ) ) {

  public static function photo($url, $width, $height = NULL, Provider $provider = NULL, $title = NULL, $author_name = NULL, $author_url = NULL, $cache_age = NULL, $thumbnail_url = NULL, $thumbnail_width = NULL, $thumbnail_height = NULL) {
    if (empty($url)) {
      throw new \InvalidArgumentException('Photo resources must provide a URL.');
    }

    $resource = static::link($url, $provider, $title, $author_name, $author_url, $cache_age, $thumbnail_url, $thumbnail_width, $thumbnail_height);
    $resource->type = self::TYPE_PHOTO;
    $resource->setDimensions($width, $height);

    return $resource;
  }

  /** * Creates a rich resource. * * @param string $html * The HTML representation of the resource. * @param int $width * The width of the resource, in pixels. * @param int $height * (optional) The height of the resource, in pixels. * @param \Drupal\media\OEmbed\Provider $provider * (optional) The resource provider. * @param string $title * (optional) A text title, describing the resource. * @param string $author_name * (optional) The name of the author/owner of the resource. * @param string $author_url * (optional) A URL for the author/owner of the resource. * @param int $cache_age * (optional) The suggested cache lifetime for this resource, in seconds. * @param string $thumbnail_url * (optional) A URL to a thumbnail image representing the resource. If this * parameter is present, $thumbnail_width and $thumbnail_height must also be * present. * @param int $thumbnail_width * (optional) The width of the thumbnail, in pixels. If this parameter is * present, $thumbnail_url and $thumbnail_height must also be present. * @param int $thumbnail_height * (optional) The height of the thumbnail, in pixels. If this parameter is * present, $thumbnail_url and $thumbnail_width must also be present. * * @return static */

    private RequestStack $requestStack;

    public function __construct(RequestStack $requestStack)
    {
        $this->requestStack = $requestStack;
    }

    public function getFunctions(): array
    {
        return [
            new TwigFunction('link', $this->link(...)),
            new TwigFunction('preload', $this->preload(...)),
            new TwigFunction('dns_prefetch', $this->dnsPrefetch(...)),
            new TwigFunction('preconnect', $this->preconnect(...)),
            new TwigFunction('prefetch', $this->prefetch(...)),
            new TwigFunction('prerender', $this->prerender(...)),
        ];
    }

    /** * Adds a "Link" HTTP header. * * @param string $rel The relation type (e.g. "preload", "prefetch", "prerender" or "dns-prefetch") * @param array $attributes The attributes of this link (e.g. "['as' => true]", "['pr' => 0.5]") * * @return string The relation URI */

$crawler->addHtmlContent($this->getDoctype().'<html><div class="foo"></html>', 'UTF-8');

        $this->assertEquals('foo', $crawler->filterXPath('//div')->attr('class'), '->addHtmlContent() adds nodes from an HTML string');
    }

    public function testAddHtmlContentWithBaseTag()
    {
        $crawler = $this->createCrawler();
        $crawler->addHtmlContent($this->getDoctype().'<html><head><base href="http://symfony.com"></head><a href="/contact"></a></html>', 'UTF-8');

        $this->assertEquals('http://symfony.com', $crawler->filterXPath('//base')->attr('href'), '->addHtmlContent() adds nodes from an HTML string');
        $this->assertEquals('http://symfony.com/contact', $crawler->filterXPath('//a')->link()->getUri(), '->addHtmlContent() adds nodes from an HTML string');
    }

    /** * @requires extension mbstring */
    public function testAddHtmlContentCharset()
    {
        $crawler = $this->createCrawler();
        $crawler->addHtmlContent($this->getDoctype().'<html><div class="foo">Tiếng Việt</html>', 'UTF-8');

        $this->assertEquals('Tiếng Việt', $crawler->filterXPath('//div')->text());
    }

        ?> <label> <?php if ( ! empty( $this->label ) ) : ?> <span class="customize-control-title"><?php echo esc_html( $this->label ); ?></span> <?php endif; ?> <?php if ( ! empty( $this->description ) ) : ?> <span class="description customize-control-description"><?php echo $this->description; ?></span> <?php endif; ?> <select <?php $this->link(); ?>> <?php                 foreach ( $this->choices as $value => $label ) :
                    echo '<option value="' . esc_attr( $value ) . '"' . selected( $this->value(), $value, false ) . '>' . $label . '</option>';
                endforeach;
                ?> </select> </label> <button type="button" class="button-link create-menu<?php echo $value_hidden_class; ?>" data-location-id="<?php echo esc_attr( $this->location_id ); ?>" aria-label="<?php esc_attr_e( 'Create a menu for this location' ); ?>"><?php _e( '+ Create New Menu' ); ?></button> <button type="button" class="button-link edit-menu<?php echo $no_value_hidden_class; ?>" aria-label="<?php esc_attr_e( 'Edit selected menu' ); ?>"><?php _e( 'Edit Menu' ); ?></button> <?php     }
}

public function testLinkIsOverwrittenIfPointsToDifferentTarget()
    {
        $this->markAsSkippedIfLinkIsMissing();

        $file = $this->workspace.\DIRECTORY_SEPARATOR.'file';
        $file2 = $this->workspace.\DIRECTORY_SEPARATOR.'file2';
        $link = $this->workspace.\DIRECTORY_SEPARATOR.'link';

        touch($file);
        touch($file2);
        link($file2, $link);

        $this->filesystem->hardlink($file, $link);

        $this->assertTrue(is_file($link));
        $this->assertEquals(fileinode($file), fileinode($link));
    }

    public function testLinkIsNotOverwrittenIfAlreadyCreated()
    {
        $this->markAsSkippedIfLinkIsMissing();

/** * Preloads a resource. * * @param string $uri A public path * @param array $attributes The attributes of this link (e.g. "array('as' => true)", "array('crossorigin' => 'use-credentials')") * * @return string The path of the asset */
    public function preload(string $uri, array $attributes = []): string
    {
        return $this->link($uri, 'preload', $attributes);
    }

    /** * Resolves a resource origin as early as possible. * * @param string $uri A public path * @param array $attributes The attributes of this link (e.g. "array('as' => true)", "array('pr' => 0.5)") * * @return string The path of the asset */
    public function dnsPrefetch(string $uri, array $attributes = []): string
    {

    // Prepare the arguments to pass to the factory method.     $provider = $data['provider_name'] ? $this->providers->get($data['provider_name']) : NULL;

    // The Resource object will validate the data we create it with and throw an     // exception if anything looks wrong. For better debugging, catch those     // exceptions and wrap them in a more specific and useful exception.     try {
      switch ($data['type']) {
        case Resource::TYPE_LINK:
          return Resource::link(
            $data['url'],
            $provider,
            $data['title'],
            $data['author_name'],
            $data['author_url'],
            $data['cache_age'],
            $data['thumbnail_url'],
            $data['thumbnail_width'],
            $data['thumbnail_height']
          );

private int $umask;

    private static ?bool $linkOnWindows = null;
    private static ?bool $symlinkOnWindows = null;

    public static function setUpBeforeClass(): void
    {
        if ('\\' === \DIRECTORY_SEPARATOR) {
            self::$linkOnWindows = true;
            $originFile = tempnam(sys_get_temp_dir(), 'li');
            $targetFile = tempnam(sys_get_temp_dir(), 'li');
            if (true !== @link($originFile, $targetFile)) {
                $report = error_get_last();
                if (\is_array($report) && str_contains($report['message'], 'error code(1314)')) {
                    self::$linkOnWindows = false;
                }
            } else {
                @unlink($targetFile);
            }

            self::$symlinkOnWindows = true;
            $originDir = tempnam(sys_get_temp_dir(), 'sl');
            $targetDir = tempnam(sys_get_temp_dir(), 'sl');

        $this->request = new Request();

        $requestStack = new RequestStack();
        $requestStack->push($this->request);

        $this->extension = new WebLinkExtension($requestStack);
    }

    public function testLink()
    {
        $this->assertEquals('/foo.css', $this->extension->link('/foo.css', 'preload', ['as' => 'style', 'nopush' => true]));

        $link = (new Link('preload', '/foo.css'))->withAttribute('as', 'style')->withAttribute('nopush', true);
        $this->assertEquals([$link], array_values($this->request->attributes->get('_links')->getLinks()));
    }

    public function testPreload()
    {
        $this->assertEquals('/foo.css', $this->extension->preload('/foo.css', ['as' => 'style', 'crossorigin' => true]));

        $link = (new Link('preload', '/foo.css'))->withAttribute('as', 'style')->withAttribute('crossorigin', true);
        $this->assertEquals([$link], array_values($this->request->attributes->get('_links')->getLinks()));
    }

        $size = filesize($temp_file['filename']);
        if ($size !== false) {
            $info = ',S=' . $size . $info;
        }
        $new_filename = $temp_file['dirname'] . DIRECTORY_SEPARATOR;
        $new_filename .= $recent ? 'new' : 'cur';
        $new_filename .= DIRECTORY_SEPARATOR . $temp_file['uniq'] . $info;

        // we're throwing any exception after removing our temp file and saving it to this variable instead         $exception = null;

        if (!link($temp_file['filename'], $new_filename)) {
            /** * @see Zend_Mail_Storage_Exception */
            $exception = new Zend_Mail_Storage_Exception('cannot link message file to final dir');
        }
        @unlink($temp_file['filename']);

        if ($exception) {
            throw $exception;
        }

    public function clickLink(string $linkText/* , array $serverParameters = [] */): Crawler
    {
        $serverParameters = 1 < \func_num_args() ? func_get_arg(1) : [];

        $crawler = $this->crawler ?? throw new BadMethodCallException(sprintf('The "request()" method must be called before "%s()".', __METHOD__));

        return $this->click($crawler->selectLink($linkText)->link(), $serverParameters);
    }

    /** * Submits a form. * * @param array $values An array of form field values * @param array $serverParameters An array of server parameters */
    public function submit(Form $form, array $values = [], array $serverParameters = []): Crawler
    {
        $form->setValues($values);

$client->request('GET', 'https://www.example.com/foo/foobar');

        $this->assertTrue($client->getCookieJar()->get('foo', '/', 'www.example.com')->isSecure());
    }

    public function testClick()
    {
        $client = $this->getBrowser();
        $client->setNextResponse(new Response('<html><a href="/foo">foo</a></html>'));
        $crawler = $client->request('GET', 'http://www.example.com/foo/foobar');

        $client->click($crawler->filter('a')->link());

        $this->assertSame('http://www.example.com/foo', $client->getRequest()->getUri(), '->click() clicks on links');
    }

    public function testClickPreserveHeaders()
    {
        $client = $this->getBrowser();
        $client->setNextResponse(new Response('<html><a href="/foo">foo</a></html>'));
        $crawler = $client->request('GET', 'http://www.example.com/foo/foobar');

        $client->click($crawler->filter('a')->link(), ['X-Special-Header' => 'Special Header Value']);