str_pad() / str_repeat() Since: PHP 4（2000）

// Pads a string to the specified length.
str_pad($string, $length, $pad_string, $pad_type);

// Repeats a string the specified number of times.
str_repeat($string, $times);

str_pad() returns the padded string. If the original string is already equal to or longer than the specified length, it is returned unchanged. str_repeat() returns the repeated string.

<?php
// Pads the right side with spaces. Right-padding is the default behavior.
echo str_pad("PHP", 10); // Outputs "PHP       " — 7 spaces are added.

// Pads the left side with zeros.
echo str_pad("42", 5, "0", STR_PAD_LEFT); // Outputs "00042".

// Pads both sides with hyphens.
echo str_pad("Title", 20, "-", STR_PAD_BOTH); // Hyphens are added on both sides.

// You can use a multi-character pad string.
echo str_pad("1", 10, "=-", STR_PAD_RIGHT); // Outputs "1=-=-=-=-=-" — the pad string repeats.

// Repeat a string with str_repeat().
echo str_repeat("*", 10); // Outputs "**********".

// Useful for generating separator lines.
echo str_repeat("-", 40); // Outputs a line of 40 hyphens.

// Useful for generating indentation.
$depth = 3;
$indent = str_repeat("  ", $depth);
echo $indent . "Nested item"; // Outputs the string preceded by 6 spaces.

// Zero-padding an order number.
$order_id = 157;
echo "ORD-" . str_pad($order_id, 6, "0", STR_PAD_LEFT); // Outputs "ORD-000157".

// Right-aligning prices in a list.
$items = ["Apple" => 150, "Orange" => 80, "Grape" => 500];
foreach ($items as $name => $price) {
	echo str_pad($name, 10) . str_pad($price, 6, " ", STR_PAD_LEFT) . "\n";
}

str_pad() pads a string with another character until it reaches the specified length. The fourth argument controls the direction: STR_PAD_RIGHT pads the right, STR_PAD_LEFT pads the left, and STR_PAD_BOTH pads both sides. When omitted, STR_PAD_RIGHT is used.

To zero-pad an order number, use str_pad($id, 6, "0", STR_PAD_LEFT) — this produces the same result as %06d in sprintf(). It is also handy for text formatting and generating fixed-width data for CSV output.

str_repeat() repeats a string a specified number of times and is useful for creating separator lines or indentation. Passing 0 returns an empty string; passing a negative value causes an error. For format-based string building, see sprintf(). For extracting substrings, see substr().