PHP calculates the SHA-1 hash function sha1() of a string

Example

Calculate the SHA-1 hash of the string "Hello":

<?php
$str = "Hello";
echo sha1($str);
?>

Definition and usage

sha1() function calculates the SHA-1 of the string hash.

The sha1() function uses the American Secure Hash algorithm 1.

Explanation from RFC 3174 - US Secure Hash Algorithm 1: SHA-1 produces a 160-bit output called the message digest. The message digest can be fed into a signature algorithm that generates or verifies the message signature. Signing the message digest instead of the message can improve process efficiency because the size of the message digest is usually much smaller than the message. The verifier of a digital signature must use the same hashing algorithm as the creator of the digital signature.

Tip: To calculate the SHA-1 hash of a file, use the sha1_file() function.

Syntax

sha1(string,raw)

Parameters Description

string Required. Specifies the string to be calculated. ​

raw ​ Optional. Specifies hexadecimal or binary output format:

            TRUE - raw 20 character binary format

                FALSE - default. 40 character hexadecimal number

Technical details

Return value:                 Returns the calculated SHA-1 hash if successful, or FALSE if failed. ​

PHP Version: ​ 4.3.0+ ​

Update Log: ​ In PHP 5.0, the raw parameter becomes optional.

More examples

Instance 1

Output the result of sha1():

<?php 
$str = "Hello"; 
echo "The string: ".$str."<br>"; 
echo "TRUE - Raw 20 character binary format: ".sha1($str, TRUE)."<br>"; 
echo "FALSE - 40 character hex number: ".sha1($str)."<br>"; 
?>

Instance 2

Output the result of sha1() Result and test it:

<?php
$str = "Hello";
echo sha1($str);

if (sha1($str) == "f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0")
{
echo "<br>Hello world!";
exit;
}
?>

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