How can string functions in PHP help with comparing and manipulating strings for conditional statements?

String functions in PHP can help with comparing and manipulating strings for conditional statements by providing various functions to easily check for substrings, compare strings, convert case, trim whitespace, and more. These functions can simplify the process of working with strings and make it easier to write conditional statements based on string values.

$string1 = "Hello";
$string2 = "hello";

// Using strtolower() to convert both strings to lowercase for case-insensitive comparison
if (strtolower($string1) === strtolower($string2)) {
    echo "Strings are equal.";
} else {
    echo "Strings are not equal.";
}