PHP md5() Function
 Complete PHP String Reference
Definition and Usage
The md5() function calculates the MD5 hash of a string.
The md5() function uses the RSA Data Security, Inc. MD5 Message-Digest
Algorithm.
From RFC 1321 -
The MD5 Message-Digest Algorithm: "The MD5 message-digest algorithm takes as
input a message of arbitrary length and produces as output a 128-bit
"fingerprint" or "message digest" of the input. The MD5 algorithm is intended for digital signature applications, where
a large file must be "compressed" in a secure manner before being encrypted with
a private (secret) key under a public-key cryptosystem such as RSA."
This function returns the calculated MD5 hash on success, or FALSE on failure.
Syntax
| Parameter |
Description |
| string |
Required. The string to be calculated |
| raw |
Optional. Specifies hex or binary output
format:
- TRUE - Raw 16 character binary format
- FALSE - Default. 32 character hex number
Note: This parameter was added in PHP 5.0 |
Example 1
<?php
$str = "Hello";
echo md5($str);
?>
|
The output of the code above will be:
|
8b1a9953c4611296a827abf8c47804d7
|
Example 2
In this example we will print the result of md5() and then test it:
<?php
$str = "Hello";
echo md5($str);
if (md5($str) == '8b1a9953c4611296a827abf8c47804d7')
{
echo "<br />Hello world!";
exit;
}
?>
|
The output of the code above will be:
8b1a9953c4611296a827abf8c47804d7
Hello world!
|
Complete PHP String Reference
 |
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