get_meta_tags

    (PHP 4, PHP 5, PHP 7, PHP 8)

    get_meta_tags — 从一个文件中提取所有的 meta 标签 content 属性，返回一个数组

    说明

    get_meta_tags(string $filename, bool $use_include_path = false): array|false

    打开 filename 逐行解析文件中的 <meta> 标签。解析工作将在 </head> 处停止。

    参数

    filename

    HTML 文件的路径字符串。 此参数可以是本地文件也可以是一个 URL。

    示例 #1 get_meta_tags() 解析了什么

    <meta name="author" content="name">
<meta name="keywords" content="php documentation">
<meta name="DESCRIPTION" content="a php manual">
<meta name="geo.position" content="49.33;-86.59">
</head> <!-- 解析工作在此处停止 -->

    use_include_path

    将 use_include_path 设置为 true 将使 PHP 尝试按照 include_path 标准包含路径中的每个指向去打开文件。这只用于本地文件，不适用于 URL。

    返回值

    返回一个数组，包含所有解析过的 meta 标签。

    返回的关联数组以属性 name 的值作为键，属性 content 的值作为值，所以你可以很容易地使用标准数组函数遍历此关联数组或访问某个值。 属性 name 中的特殊字符将使用‘_’替换，而其它字符则转换成小写。如果有两个 meta 标签拥有相同的 name，则只返回最后出现的那一个。

    失败时返回 false 。

    示例

    示例 #2 get_meta_tags() 返回了什么

    <?php
    // 假设上边的标签是在 www.example.com 中
    $tags = get_meta_tags('http://www.example.com/');

    // 注意所有的键（key）均为小写，而键中的‘.’则转换成了‘_’。
    echo $tags['author']; // name
    echo $tags['keywords']; // php documentation
    echo $tags['description']; // a php manual
    echo $tags['geo_position']; // 49.33;-86.59
    ?>

    注释

    注意:

    只有包含 name 属性的 meta 标签才会被解析。不需要引号。

    参见

    改进此页面

    了解如何改进此页面 • 提交拉取请求 • 报告一个错误
    ＋添加备注

    用户贡献的备注 19 notes

    up
    51
    bobble bubble
    9 years ago
    This regex gets meta tags independent of sequence by capturing inside a lookahead.
    Further uses the branch reset feature for different quote styles of values.
    The pattern can be tested here: https://regex101.com/r/oE4oU9/1

    <?PHP

    function getMetaTags($str)
    {
    $pattern = '
    ~<\s*meta\s

    # using lookahead to capture type to $1
    (?=[^>]*?
    \b(?:name|property|http-equiv)\s*=\s*
    (?|"\s*([^"]*?)\s*"|\'\s*([^\']*?)\s*\'|
    ([^"\'>]*?)(?=\s*/?\s*>|\s\w+\s*=))
    )

    # capture content to $2
    [^>]*?\bcontent\s*=\s*
    (?|"\s*([^"]*?)\s*"|\'\s*([^\']*?)\s*\'|
    ([^"\'>]*?)(?=\s*/?\s*>|\s\w+\s*=))
    [^>]*>

    ~ix'    ;

    if(    preg_match_all($pattern, $str, $out))
    return     array_combine($out[1], $out[2]);
    return array();
    }

    // usage
    $meta_tags = getMetaTags($str);

    ?>
    up
    7
    richard dot dern at athaliasoft dot fr
    11 years ago
    I personally experienced less issues using the DOM functions than regular expressions while trying to fetch meta tags and not using get_meta_tags function (in order to get http-equiv meta tags too).

    <?php

    $doc     = new DOMDocument();
    $doc->loadHTML($html);

    $xpath = new DOMXPath($doc);

    $nodes = $xpath->query('//head/meta');

    foreach(    $nodes as $node) {
    [...]
    }

    ?>
    up
    3
    jp at webgraphe dot com
    20 years ago
    If the URL is doing a redirection using the headers (like you would do with PHP function header("Location: URL");), the page has no content (in general). It appears get_meta_tags() doesn't catch that kind of redirection (like cURL would do) and it lead me to a timeout of my script.

    I experienced this in a spider I wrote in order to feed my database of all available pages on my site and one link was linking to a page that simply has the following code:

    <?php
    header    ("Location: sections.php?section=home");
    exit();
    ?>

    That made my script hang for a moment and apparently, get_meta_tags() wasn't even able to return me an error.

    JP.
    up
    2
    Ebpo
    11 years ago
    Be aware that the function looks for the metatags in the whole page. If one of the meta is commented in your code for some reason, it will still be grabed.
    up
    2
    Anonymous
    22 years ago
    Tested PHP 4.0.6

    get_meta_tags() seems to look only in the beginning of a file, meaning that e.g. if there is a lot of PHP code before the HTML header it will return nothing ...
    Tested using get_meta_tags() on local files with about 9000 characters of PHP code before HTML HEADER.

    Workaround: if possible move code after header or if not: include a file.
    up
    2
    richard at pifmagazine dot com
    24 years ago
    An Important Note about META tags and this function : if your META tag contains newline "\n" characters, get_meta_tags() will return a NULL value for that name property. Removing the newlines from the source META tag corrects the problem.
    up
    8
    LWC
    9 years ago
    New version based on mariano at cricava dot com's work with:
    1) Support for Meta properties (like Facebook's og tags).
    2) Support for Unicode (UTF-8) encoded Meta lines.
    3) An option not to convert htmlentities - if you plan to actually use the results and not just display them.

    function getUrlData($url, $raw=false) // $raw - enable for raw display
    {
    $result = false;

    $contents = getUrlContents($url);

    if (isset($contents) && is_string($contents))
    {
    $title = null;
    $metaTags = null;
    $metaProperties = null;

    preg_match('/<title>([^>]*)<\/title>/si', $contents, $match );

    if (isset($match) && is_array($match) && count($match) > 0)
    {
    $title = strip_tags($match[1]);
    }

    preg_match_all('/<[\s]*meta[\s]*(name|property)="?' . '([^>"]*)"?[\s]*' . 'content="?([^>"]*)"?[\s]*[\/]?[\s]*>/si', $contents, $match);

    if (isset($match) && is_array($match) && count($match) == 4)
    {
    $originals = $match[0];
    $names = $match[2];
    $values = $match[3];

    if (count($originals) == count($names) && count($names) == count($values))
    {
    $metaTags = array();
    $metaProperties = $metaTags;
    if ($raw) {
    if (version_compare(PHP_VERSION, '5.4.0') == -1)
    $flags = ENT_COMPAT;
    else
    $flags = ENT_COMPAT | ENT_HTML401;
    }

    for ($i=0, $limiti=count($names); $i < $limiti; $i++)
    {
    if ($match[1][$i] == 'name')
    $meta_type = 'metaTags';
    else
    $meta_type = 'metaProperties';
    if ($raw)
    ${$meta_type}[$names[$i]] = array (
    'html' => htmlentities($originals[$i], $flags, 'UTF-8'),
    'value' => $values[$i]
    );
    else
    ${$meta_type}[$names[$i]] = array (
    'html' => $originals[$i],
    'value' => $values[$i]
    );
    }
    }
    }

    $result = array (
    'title' => $title,
    'metaTags' => $metaTags,
    'metaProperties' => $metaProperties,
    );
    }

    return $result;
    }

    function getUrlContents($url, $maximumRedirections = null, $currentRedirection = 0)
    {
    $result = false;

    $contents = @file_get_contents($url);

    // Check if we need to go somewhere else

    if (isset($contents) && is_string($contents))
    {
    preg_match_all('/<[\s]*meta[\s]*http-equiv="?REFRESH"?' . '[\s]*content="?[0-9]*;[\s]*URL[\s]*=[\s]*([^>"]*)"?' . '[\s]*[\/]?[\s]*>/si', $contents, $match);

    if (isset($match) && is_array($match) && count($match) == 2 && count($match[1]) == 1)
    {
    if (!isset($maximumRedirections) || $currentRedirection < $maximumRedirections)
    {
    return getUrlContents($match[1][0], $maximumRedirections, ++$currentRedirection);
    }

    $result = false;
    }
    else
    {
    $result = $contents;
    }
    }

    return $contents;
    }
    ?>

    <?php
    $result     = getUrlData('http://whatever...', true);

    echo     '<pre>'; print_r($result, true); echo '</pre>';

    ?>

    Output example:

    <?php
    Array
    (
    [    title] => The requested page's title
    [metaTags] => Array
    (
    [description] => Array
    (
    [html] => <meta name="description" content="Something..." />
    [value] => Something...
    )
    )
    [metaProperties] => Array
    (
    [og:type] => Array
    (
    [html] => <meta property="og:type" content="article"/>/>
    [value] => article
    )
    )
    )
    ?>
    up
    1
    rehfeld
    19 years ago
    in response to
    jp at webgraphe dot com

    this function grabs meta tags, not http headers

    if you need the headers

    <?php

    $fp     = fopen('http://example.org/somepage.html', 'r');

    // the variable $http_response_header magically appears
    print_r($http_response_header);

    // or
    $meta_data = stream_get_meta_data($fp);
    print_r($meta_data);

    ?>
    up
    5
    mariano at cricava dot com
    19 years ago
    Based on Michael Knapp's code, and adding some regex, here's a function that will get all meta tags and the title based on a URL. If there's an error, it will return false. Using the function getUrlContents(), also included, it takes care of META REFRESH re-directions, following up to the specified number of redirections. Please note that the regular expressions included were split into strings because php.net was complaining about the line being to long ;)

    <?php
    function getUrlData($url)
    {
    $result = false;

    $contents = getUrlContents($url);

    if (isset(    $contents) && is_string($contents))
    {
    $title = null;
    $metaTags = null;

    preg_match('/<title>([^>]*)<\/title>/si', $contents, $match );

    if (isset(    $match) && is_array($match) && count($match) > 0)
    {
    $title = strip_tags($match[1]);
    }

    preg_match_all('/<[\s]*meta[\s]*name="?' . '([^>"]*)"?[\s]*' . 'content="?([^>"]*)"?[\s]*[\/]?[\s]*>/si', $contents, $match);

    if (isset(    $match) && is_array($match) && count($match) == 3)
    {
    $originals = $match[0];
    $names = $match[1];
    $values = $match[2];

    if (    count($originals) == count($names) && count($names) == count($values))
    {
    $metaTags = array();

    for (    $i=0, $limiti=count($names); $i < $limiti; $i++)
    {
    $metaTags[$names[$i]] = array (
    'html' => htmlentities($originals[$i]),
    'value' => $values[$i]
    );
    }
    }
    }

    $result = array (
    'title' => $title,
    'metaTags' => $metaTags
    );
    }

    return     $result;
    }

    function     getUrlContents($url, $maximumRedirections = null, $currentRedirection = 0)
    {
    $result = false;

    $contents = @file_get_contents($url);

    // Check if we need to go somewhere else

    if (isset($contents) && is_string($contents))
    {
    preg_match_all('/<[\s]*meta[\s]*http-equiv="?REFRESH"?' . '[\s]*content="?[0-9]*;[\s]*URL[\s]*=[\s]*([^>"]*)"?' . '[\s]*[\/]?[\s]*>/si', $contents, $match);

    if (isset(    $match) && is_array($match) && count($match) == 2 && count($match[1]) == 1)
    {
    if (!isset(    $maximumRedirections) || $currentRedirection < $maximumRedirections)
    {
    return     getUrlContents($match[1][0], $maximumRedirections, ++$currentRedirection);
    }

    $result = false;
    }
    else
    {
    $result = $contents;
    }
    }

    return     $contents;
    }
    ?>

    Here's an example of its usage. Check that the included URL has a META REFRESH redirection:

    <?php
    $result     = getUrlData('http://www.marianoiglesias.com.ar/');

    echo     '<pre>'; print_r($result); echo '</pre>';

    ?>

    For the above code the output would be:

    <?php
    Array
    (
    [    title] => Mariano Iglesias: El Eternauta
    [metaTags] => Array
    (
    [    description] => Array
    (
    [    html] => <meta name="description" content="Java, PHP, and some other technological mumble jumble. Also, some real-life stuff as well." />
    [    value] => Java, PHP, and some other technological mumble jumble. Also, some real-life stuff as well.
    )

    [    DC.title] => Array
    (
    [    html] => <meta name="DC.title" content="Mariano Iglesias - Weblog" />
    [    value] => Mariano Iglesias - Weblog
    )

    [    ICBM] => Array
    (
    [    html] => <meta name="ICBM" content="-34.6017, -58.3956" />
    [    value] => -34.6017, -58.3956
    )

    [    geo.position] => Array
    (
    [    html] => <meta name="geo.position" content="-34.6017;-58.3956" />
    [    value] => -34.6017;-58.3956
    )

    [    geo.region] => Array
    (
    [    html] => <meta name="geo.region" content="AR-BA">
    [    value] => AR-BA
    )

    [    geo.placename] => Array
    (
    [    html] => <meta name="geo.placename" content="Buenos Aires">
    [    value] => Buenos Aires
    )

    )

    )
    ?>
    up
    4
    roganty at gmail dot com
    18 years ago
    This is a slight amendment to jimmyxx at gmail dot com function

    I tried using the regex displayed in his code, and php threw up a couple of errors

    Below is the correct regular expression that works
    (Please note that I had to split the regex into strings because php.net was complaining about the line being to long)
    <?php
    preg_match_all    (
    "|<meta[^>]+name=\"([^\"]*)\"[^>]" . "+content=\"([^\"]*)\"[^>]+>|i",
    $html, $out,PREG_PATTERN_ORDER);
    ?>

    The problem was due to the quotes being incorrectly escaped.
    I hope this helps anyone who has been having problems with his code
    up
    1
    tim dot bennett at haveaniceplay dot com
    19 years ago
    If you want to get the contents of tags other than meta you can use:

    <?php

    $page     = "http://www.mysite.com/apage.php";

    // tags
    $start = '<atag>';
    $end = '<\/atag>';

    // open the file
    $fp = fopen( $page, 'r' );

    $cont = "";

    // read the contents
    while( !feof( $fp ) ) {
    $buf = trim( fgets( $fp, 4096 ) );
    $cont .= $buf;
    }

    // get tag contents
    preg_match( "/$start(.*)$end/s", $cont, $match );

    // tag contents
    $contents = $match[ 1 ];

    ?>
    up
    0
    Michael Knapp
    19 years ago
    Tim's code is good (thanks Tim), except it won't work very well if the tag is part of a long non-breaking string.

    E.g. try getting the title from Google Maps (http://www.google.com/maps).

    A better solution is:

    <?php
    $title     = "";

    if (    $fp = @fopen( $_POST['url'], 'r' )) {

    $cont = "";

    // read the contents
    while( !feof( $fp ) ) {
    $buf = trim(fgets( $fp, 4096 )) ;
    $cont .= $buf;
    }

    // get tag contents
    @preg_match( "/<title>([a-z 0-9]*)<\/title>/si", $cont, $match );

    // tag contents
    $title = strip_tags(@$match[ 1 ]);
    }

    ?>

    Note the strip_tags. Another thing to be careful of is to check for ", <, and >. You will need to strip those out if you are posting the output to a form.

    Also, it is probably best to use the /i modifier, because some people might code <TITLE> etc...
    up
    0
    richard at pifmagazine dot com
    24 years ago
    Something that is not mentioned above and should be : When using get_meta_tags on a remote PHP page the page will be parsed before the meta tags are returned - so you can capture meta tags generated dynamically (by PHP??) on the remote end.

    This DOES NOT work the same way when getting meta tags on local file systems. Local files are not parsed through the web server before returning to get_meta_tags(). If the META tag is hard-coded into the page, you'll be fine - but if it dynamically generated you will not be able to capture it unless you use the full URL when calling your local files.
    up
    -2
    doob_ at gmx dot de
    15 years ago
    <?php

    /*
    ** Extracts and formats meta tag content
    */

    function get_meta_data($url, $searchkey='') {
    $data = get_meta_tags($url); // get the meta data in an array
    foreach($data as $key => $value) {
    if(    mb_detect_encoding($value, 'UTF-8, ISO-8859-1', true) != 'ISO-8859-1') { // check whether the content is UTF-8 or ISO-8859-1
    $value = utf8_decode($value); // if UTF-8 decode it
    }
    $value = strtr($value, get_html_translation_table(HTML_ENTITIES)); // mask the content
    if($searchkey != '') { // if only one meta tag is in demand e.g. 'description'
    if($key == $searchkey) {
    $str = $value; // just return the value
    }
    } else {     // all meta tags
    $pattern = '/ |,/i'; // ' ' or ','
    $array = preg_split($pattern, $value, -1, PREG_SPLIT_NO_EMPTY); // split it in an array, so we have the count of words
    $str .= '<p><span style="display:block;color:#000000;font-weight:bold;">' . $key . ' <span style="font-weight:normal;">(' . count($array) . ' words | ' . strlen($value) . ' chars)</span></span>' . $value . '</p>'; // format data with count of words and chars
    }
    }
    return     $str;
    }

    $content .= get_meta_data("http://www.example.com/");
    /*
    output looks like this:

    description (23 words | 167 chars)
    SELFHTML 8.1.2 - Die bekannte Dokumentation zu HTML, JavaScript und CGI/Perl - Tutorial und Referenz, mit etlichen Zusatztips zu Design, Grafik, Projektverwaltung usw.

    keywords (13 words | 119 chars)
    SELFHTML, HTML, Dynamic HTML, JavaScript, CGI, Perl, Grafik, WWW-Seiten, Web-Seiten, Hilfe, Dokumentation, Beschreibung

    etc.

    */

    $content .= get_meta_data("http://www.example.com/", "description");
    /*
    output looks like this:

    SELFHTML 8.1.2 - Die bekannte Dokumentation zu HTML, JavaScript und CGI/Perl - Tutorial und Referenz, mit etlichen Zusatztips zu Design, Grafik, Projektverwaltung usw.
    */

    ?>
    up
    -1
    jstel at 126 dot com
    15 years ago
    this function could get each meta of html content , and stripped all js and css.

    <?php
    function get_meta_data($content)
    {
    $content = strtolower($content);
    $content = preg_replace("'<style[^>]*>.*</style>'siU",'',$content); // strip js
    $content = preg_replace("'<script[^>]*>.*</script>'siU",'',$content); // strip css
    $split = explode("\n",$content);
    foreach (    $split as $k => $v)
    {
    if (    strpos(' '.$v,'<meta')) {
    preg_match_all(
    "/<meta[^>]+(http\-equiv|name)=\"([^\"]*)\"[^>]" . "+content=\"([^\"]*)\"[^>]*>/i",
    $v, $split_content[],PREG_PATTERN_ORDER);;
    }
    }
    return     $split_content;
    }
    ?>
    up
    -1
    Antonio - Malaga
    15 years ago
    It's not work if meta syntax not have trailing slash.
    up
    -1
    Ben dot Davis at furman dot edu
    23 years ago
    I have found that for large searches, get_meta_tags is very slow. I created a large search engine for a website that couldnt use a database and I first tried pulling out the meta tags.
    I have found that it is actually much faster to use eregi to pull out the meta tags. This code below pulls out the description:

    if (eregi ("<meta name=\"description\" content=[^>]*", $contents, $descresult))
    {
    $description = explode("<meta name=\"description\" content=", $descresult[0]);
    echo "<font face=\"Arial\" size=2>$description[1]</font>";

    }
    up
    -3
    diel at caroes dot be
    16 years ago
    Quick meta data grabber
    [code]
    if(get_meta_tags('http://'.$_POST['pagina'])){
    print '<font class="midden">Meta data from http://'.$_POST['pagina'].'</font>';
    $metadata = get_meta_tags('http://'.$_POST['pagina']);
    echo '<table width="100%">';
    print '<tr><td>Meta</td><td>Waarde</td></tr>';
    foreach($metadata as $naam => $waarde){
    echo '<tr><td valign="top">'.$naam.'</td><td>'.$waarde.'</td></tr>';
    }
    print '</table>';
    }else{
    print '
    <div class="red_h">Incorrect</div>
    ';
    }
    [/code]
    up
    -3
    jimmyxx at gmail dot com
    19 years ago
    I used this as part of my mini php search based search engine - it really slowed the whole thing down. I wrote this function to read HTML (just fetch the file or use something like snoopy) and extract the meta data via a simple regex, works a treat and made my crawler much faster:

    <?php

    function get_meta_data($html) {

    preg_match_all(
    "|<meta[^>]+name=\\"([^\\"]*)\\"[^>]+content=\\"([^\\"]*)\\"[^>]+>|i", $html, $out,PREG_PATTERN_ORDER);

    for (    $i=0;$i < count($out[1]);$i++) {
    // loop through the meta data - add your own tags here if you need
    if (strtolower($out[1][$i]) == "keywords") $meta['keywords'] = $out[2][$i];
    if (    strtolower($out[1][$i]) == "description") $meta['description'] = $out[2][$i];
    }

    return     $meta;
    }

    ?>
    ＋添加备注
    To Top