How can whitespace in string comparisons affect the outcome in PHP programming?

Whitespace in string comparisons can affect the outcome because PHP considers whitespace characters such as spaces, tabs, and newlines as part of the string. This means that even if two strings look the same to the human eye, they may not be considered equal by PHP due to differences in whitespace. To solve this issue, you can use functions like trim() to remove leading and trailing whitespace from the strings before comparing them.

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

if (trim($string1) === trim($string2)) {
    echo "Strings are equal after removing whitespace.";
} else {
    echo "Strings are not equal after removing whitespace.";
}