str_contains('STRING', 'SUB_STRING');

$a = 'How are you?';

​

if (strpos($a, 'are') !== false) {

    echo 'true';

}

​

phpCopy<?php

$mystring = "This is a PHP program.";

​

if (strpos($mystring, "program.") !== false) {

    echo("True");

}

?>

​

$string = "Hello123";

$containsLetters = preg_match("/[a-z]/i", $string);

​

if ($containsLetters) {

    echo "The string contains letters.";

} else {

    echo "The string does not contain any letters.";

}

$string = "Hello World";

$substring = "World";

​

if (strpos($string, $substring) !== false) {

    echo "The string contains the substring";

} else {

    echo "The string does not contain the substring";

}

$string = "This is a sample string.";

$substring = "sample";

​

// Case-insensitive search

if (strpos(strtolower($string), strtolower($substring)) !== false) {

    echo "Substring found in the string.";

} else {

    echo "Substring not found in the string.";

}

phpCopy<?php

$mystring = "This is a php program.";

$search = "a";

if(preg_match("/{$search}/i", $mystring)) {

    echo "True"; } else {

    echo("False");

}

?>

​

phpCopy<?php

$mystring = "This is a PHP program.";

​

if (strpos($mystring, "PHP", 13) !== false) {

    echo("True");

} else {

    echo("False");

}

?>

​