| Function | Description |
|---|---|
strlen($s) | Length |
strtoupper($s) | Uppercase |
strtolower($s) | Lowercase |
trim($s) | Remove whitespace |
str_replace($a,$b,$s) | Replace |
strpos($s,$find) | Position of substring |
substr($s,$start,$len) | Substring |
str_contains($s,$sub) | Contains? (PHP 8) |
explode($sep,$s) | String to array |
implode($sep,$arr) | Array to string |
sprintf($fmt,...) | Format string |
<?php
$str = " Hello, World! ";
echo strlen($str); // 17
echo trim($str); // "Hello, World!"
echo strtoupper($str); // " HELLO, WORLD! "
echo str_replace("World","PHP",$str); // replaces
$parts = explode(",", "a,b,c"); // ["a","b","c"]
echo implode(" | ", $parts); // "a | b | c"
echo sprintf("%.2f", 3.14159); // "3.14"
echo str_pad("42", 5, "0", STR_PAD_LEFT); // "00042"
?>