今天就跟大家聊聊有关使用PHP怎么从一个文本字符串中提取关键字，可能很多人都不太了解，为了让大家更加了解，小编给大家总结了以下内容，希望大家根据这篇文章可以有所收获。
function extract_keywords($str, $minWordLen = 3, $minWordOccurrences = 2, $asArray = false)
{
function keyword_count_sort($first, $sec)
{
return $sec[1] - $first[1];
}
$str = preg_replace('/[^\\w0-9 ]/', ' ', $str);
$str = trim(preg_replace('/\s+/', ' ', $str));
$words = explode(' ', $str);
$keywords = array();
while(($c_word = array_shift($words)) !== null)
{
if(strlen($c_word) <= $minWordLen) continue;
$c_word = strtolower($c_word);
if(array_key_exists($c_word, $keywords)) $keywords[$c_word][1]++;
else $keywords[$c_word] = array($c_word, 1);
}
usort($keywords, 'keyword_count_sort');
$final_keywords = array();
foreach($keywords as $keyword_det)
{
if($keyword_det[1] < $minWordOccurrences) break;
array_push($final_keywords, $keyword_det[0]);
}
return $asArray ? $final_keywords : implode(', ', $final_keywords);
}
//How to use
//Basic lorem ipsum text to extract the keywords
$text = "
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Curabitur eget ipsum ut lorem laoreet porta a non libero.
Vivamus in tortor metus. Suspendisse potenti. Curabitur
metus nisi, adipiscing eget placerat suscipit, suscipit
vitae felis. Integer eu odio enim, sed dignissim lorem.
In fringilla molestie justo, vitae varius risus lacinia ac.
Nulla porttitor justo a lectus iaculis ut vestibulum magna
egestas. Ut sed purus et nibh cursus fringilla at id purus.
";
//Echoes: lorem, suscipit, metus, fringilla, purus, justo, eget, vitae, ipsum, curabitur, adipiscing
echo extract_keywords($text);看完上述内容，你们对使用PHP怎么从一个文本字符串中提取关键字有进一步的了解吗？如果还想了解更多知识或者相关内容，请关注创新互联行业资讯频道，感谢大家的支持。
