How to search text using php if ($text contains "World") - php

Question

How to search text using php?
Something like:
<?php
$text = "Hello World!";
if ($text contains "World") {
echo "True";
}
?>
Except replacing if ($text contains "World") { with a working condition.

Answer 1

In your case you can just use strpos(), or stripos() for case insensitive search:
if (stripos($text, "world") !== false) {
echo "True";
}

Answer 2

What you need is strstr()(or stristr(), like LucaB pointed out). Use it like this:
if(strstr($text, "world")) {/* do stuff */}

Answer 3

If you are looking an algorithm to rank search results based on relevance of multiple words here comes a quick and easy way of generating search results with PHP only.
Implementation of the vector space model in PHP
function get_corpus_index($corpus = array(), $separator=' ') {
$dictionary = array();
$doc_count = array();
foreach($corpus as $doc_id => $doc) {
$terms = explode($separator, $doc);
$doc_count[$doc_id] = count($terms);
// tf–idf, short for term frequency–inverse document frequency,
// according to wikipedia is a numerical statistic that is intended to reflect
// how important a word is to a document in a corpus
foreach($terms as $term) {
if(!isset($dictionary[$term])) {
$dictionary[$term] = array('document_frequency' => 0, 'postings' => array());
}
if(!isset($dictionary[$term]['postings'][$doc_id])) {
$dictionary[$term]['document_frequency']++;
$dictionary[$term]['postings'][$doc_id] = array('term_frequency' => 0);
}
$dictionary[$term]['postings'][$doc_id]['term_frequency']++;
}
//from http://phpir.com/simple-search-the-vector-space-model/
}
return array('doc_count' => $doc_count, 'dictionary' => $dictionary);
}
function get_similar_documents($query='', $corpus=array(), $separator=' '){
$similar_documents=array();
if($query!=''&&!empty($corpus)){
$words=explode($separator,$query);
$corpus=get_corpus_index($corpus);
$doc_count=count($corpus['doc_count']);
foreach($words as $word) {
$entry = $corpus['dictionary'][$word];
foreach($entry['postings'] as $doc_id => $posting) {
//get term frequency–inverse document frequency
$score=$posting['term_frequency'] * log($doc_count + 1 / $entry['document_frequency'] + 1, 2);
if(isset($similar_documents[$doc_id])){
$similar_documents[$doc_id]+=$score;
}
else{
$similar_documents[$doc_id]=$score;
}
}
}
// length normalise
foreach($similar_documents as $doc_id => $score) {
$similar_documents[$doc_id] = $score/$corpus['doc_count'][$doc_id];
}
// sort fro high to low
arsort($similar_documents);
}
return $similar_documents;
}
IN YOUR CASE
$query = 'world';
$corpus = array(
1 => 'hello world',
);
$match_results=get_similar_documents($query,$corpus);
echo '<pre>';
print_r($match_results);
echo '</pre>';
RESULTS
Array
(
[1] => 0.79248125036058
)
MATCHING MULTIPLE WORDS AGAINST MULTIPLE PHRASES
$query = 'hello world';
$corpus = array(
1 => 'hello world how are you today?',
2 => 'how do you do world',
3 => 'hello, here you are! how are you? Are we done yet?'
);
$match_results=get_similar_documents($query,$corpus);
echo '<pre>';
print_r($match_results);
echo '</pre>';
RESULTS
Array
(
[1] => 0.74864218272161
[2] => 0.43398500028846
)
from How do I check if a string contains a specific word in PHP?

Answer 4

This might be what you are looking for:
<?php
$text = 'This is a Simple text.';
// this echoes "is is a Simple text." because 'i' is matched first
echo strpbrk($text, 'mi');
// this echoes "Simple text." because chars are case sensitive
echo strpbrk($text, 'S');
?>
Is it?
Or maybe this:
<?php
$mystring = 'abc';
$findme   = 'a';
$pos = strpos($mystring, $findme);
// Note our use of ===.  Simply == would not work as expected
// because the position of 'a' was the 0th (first) character.
if ($pos === false) {
    echo "The string '$findme' was not found in the string '$mystring'";
} else {
    echo "The string '$findme' was found in the string '$mystring'";
    echo " and exists at position $pos";
}
?>
Or even this
<?php
$email = 'name#example.com';
$domain = strstr($email, '#');
echo $domain; // prints #example.com
$user = strstr($email, '#', true); // As of PHP 5.3.0
echo $user; // prints name
?>
You can read all about them in the documentation here:
http://php.net/manual/en/book.strings.php

Answer 5

in my opinion strstr() is better than strpos(). because strstr() is compatible with both PHP 4 AND PHP 5. but strpos() is only compatible with PHP 5. please note that part of servers have no PHP 5

Answer 6

/* https://ideone.com/saBPIe */
function search($search, $string) {
$pos = strpos($string, $search);
if ($pos === false) {
return "not found";
} else {
return "found in " . $pos;
}
}
echo search("world", "hello world");
Embed PHP online:
body, html, iframe {
width: 100% ;
height: 100% ;
overflow: hidden ;
}
<iframe src="https://ideone.com/saBPIe" ></iframe>

Answer 7

The best solution is my method:
In my method, only full words are detected,But in other ways it is not.
for example:
$text='hello world!';
if(strpos($text, 'wor') === FALSE) {
echo '"wor" not found in string';
}
Result: strpos returned true!!! but in my method return false.
My method:
public function searchInLine($txt,$word){
$txt=strtolower($txt);
$word=strtolower($word);
$word_length=strlen($word);
$string_length=strlen($txt);
if(strpos($txt,$word)!==false){
$indx=strpos($txt,$word);
$last_word=$indx+$word_length;
if($indx==0){
if(strpos($txt,$word." ")!==false){
return true;
}
if(strpos($txt,$word.".")!==false){
return true;
}
if(strpos($txt,$word.",")!==false){
return true;
}
if(strpos($txt,$word."?")!==false){
return true;
}
if(strpos($txt,$word."!")!==false){
return true;
}
}else if($last_word==$string_length){
if(strpos($txt," ".$word)!==false){
return true;
}
if(strpos($txt,".".$word)!==false){
return true;
}
if(strpos($txt,",".$word)!==false){
return true;
}
if(strpos($txt,"?".$word)!==false){
return true;
}
if(strpos($txt,"!".$word)!==false){
return true;
}
}else{
if(strpos($txt," ".$word." ")!==false){
return true;
}
if(strpos($txt," ".$word.".")!==false){
return true;
}
if(strpos($txt," ".$word.",")!==false){
return true;
}
if(strpos($txt," ".$word."!")!==false){
return true;
}
if(strpos($txt," ".$word."?")!==false){
return true;
}
}
}
return false;
}