How to Implement `startsWith()` and `endsWith()` Functions in PHP?

Implementing startsWith() and endsWith() Functions in PHP

In PHP, you can create custom functions to check if a string begins or ends with a specific character or string. Here's how you can write these functions:

startsWith() Function:

function startsWith($haystack, $needle) {
    $length = strlen($needle);
    return substr($haystack, 0, $length) === $needle;
}

This function takes two parameters: the haystack (the string to check) and the needle (the character or string you're looking for at the start). It checks if the substring of the haystack starting from position 0 has a length equal to the needle and matches the needle. If true, it means the string starts with the needle.

Example:

$str = '|apples}';
echo startsWith($str, '|'); // Returns true

endsWith() Function:

function endsWith($haystack, $needle) {
    $length = strlen($needle);
    if (!$length) {
        return true;
    }
    return substr($haystack, -$length) === $needle;
}

This function works similarly, except it checks the substring of the haystack from the end of the string (-$length). If the substring matches the needle, it means the string ends with the needle.

Example:

$str = '|apples}';
echo endsWith($str, '}'); // Returns true

PHP 8.0 and Higher:

From PHP 8.0 onwards, there are built-in functions str_starts_with and str_ends_with that provide the same functionality.

var_dump(str_starts_with('|apples}', '|')); // Returns true
var_dump(str_ends_with('|apples}', '}')); // Returns true

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