Check if multiple words exist in a sentence - php

Question

I have the following :
Sentence :
"This is a red apple"
pattern to check :
red & apple.
Both sentence and pattern to check are user generated.
$sentence = "This is a red apple";
$words = array('red','apple');
$ch = implode("|",$words);
$pattern = '/[$ch]/';
if(preg_match($pattern, $sentence))
{
// Do something if the sentence contains red & apple
}
When i execute that code, i get nothing (nothing is displayed). When i do echo on $pattern it returns it as a whole string instead.
How can i fix this ? What am i missing ?

Answer 1

change $pattern = '/[$ch]/';
to
$pattern = '/('.$ch.')/'; or $pattern = '/['.$ch.']';
<?php
$sentence = "This is a red apple";
$words = array('apple','red');
$ch = implode("|",$words);
echo $pattern = '/('.$ch.')/';
if(preg_match($pattern, $sentence))
{
echo ' Do something if the sentence contains red & apple';
}else
{
echo 'nothing happpen';
}
?>
check if both word match
<?php
$sentence = "This is a red apple";
$words = array('red','apple');
$ch = implode("|",$words);
echo $pattern = '['.$ch.']';
if(preg_match_all($pattern, $sentence,$matches) == 2)
{
echo ' Do something if the sentence contains red & apple';
}else
{
echo 'nothing happpen';
}
?>
You also check how many word matched using
echo count($matches[0]);
$matches is array contain word are matched

Answer 2

You need to take care about quotes while using variables within quotes you need to update
$pattern = '/[$ch]/';
into
$pattern = "/($ch)/";
^^ ^^ ^^ ^^
You need to update your regex pattern also, so your code looks like as
$sentence = "This is a red apple";
$words = array('red','apple');
$ch = implode("|",$words);
$pattern = "/($ch)/";
if(preg_match_all($pattern, $sentence,$m))
{
echo "yes \n";
print_r($m);
}
Instead of regex I'll use array_intersect along with str_word_count like as
$sentence = "This is a red apple";
$words = array('red','apple','blue');
$var = count(array_intersect(str_word_count($sentence,1),$words));
if(count($words == $var)){
echo "Yes got it";
}
Demo
Demo2