Calculates the crc32 polynomial of a string

count_chars
crypt
String Functions
PHP Manual

# crc32

(PHP 4 >= 4.0.1, PHP 5)

crc32 — Calculates the crc32 polynomial of a string

### Description

int crc32 ( string `$str` )

Generates the cyclic redundancy checksum polynomial of 32-bit lengths of the `str`. This is usually used to validate the integrity of data being transmitted.

Because PHP's integer type is signed, and many crc32 checksums will result in negative integers, you need to use the "%u" formatter of sprintf() or printf() to get the string representation of the unsigned crc32 checksum.

### Parameters

`str`

  The data.

### Return Values

Returns the crc32 checksum of `str` as an integer.

### Examples

Example #1 Displaying a crc32 checksum

This example shows how to print a converted checksum with the printf() function:

`<?php
$checksum = crc32("The quick brown fox jumped over the lazy dog.");
printf("%u\n", $checksum);
?>`

### See Also

- md5() - Calculate the md5 hash of a string
- sha1() - Calculate the sha1 hash of a string

count_chars
crypt
String Functions
PHP Manual