String Functions
PHP Manual

fprintf

(PHP 5, PHP 7)

fprintf — Write a formatted string to a stream

Description

int fprintf ( resource $handle , string $format [, mixed $args [, mixed $... ]] )

Write a string produced according to format to the stream resource specified by handle.

Parameters

handle

A file system pointer resource that is typically created using fopen().

format

See sprintf() for a description of format.

args

...

Return Values

Returns the length of the string written.

Examples

Example #1 fprintf(): zero-padded integers

<?php
if (!($fp = fopen('date.txt', 'w'))) {
    return;
}

fprintf($fp, "%04d-%02d-%02d", $year, $month, $day);
// will write the formatted ISO date to date.txt
?>

Example #2 fprintf(): formatting currency

<?php
if (!($fp = fopen('currency.txt', 'w'))) {
    return;
}

$money1 = 68.75;
$money2 = 54.35;
$money = $money1 + $money2;
// echo $money will output "123.1";
$len = fprintf($fp, '%01.2f', $money);
// will write "123.10" to currency.txt

echo "wrote $len bytes to currency.txt";
// use the return value of fprintf to determine how many bytes we wrote
?>

See Also

String Functions
PHP Manual