php substring exists in string code example

Example 1: How do I check if a string contains a specific word?

$a = 'Hello world?';

if (strpos($a, 'Hello') !== false) { //PAY ATTENTION TO !==, not !=
    echo 'true';
}
if (stripos($a, 'HELLO') !== false) { //Case insensitive
    echo 'true';
}

Example 2: php find if substring is in string

$result = strpos("haystack", "needle");

if ($result != false)
{
  // text found
}

Example 3: php string contains

$mystring = 'abc';
$findme   = 'a';
$pos = strpos($mystring, $findme);

Example 4: php check if string contains

// returns true if $needle is a substring of $haystack
function contains($haystack, $needle){
    return strpos($haystack, $needle) !== false;
}