Blog : PHP sha1() Function

PHP sha1() Function

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 Complete PHP String Reference
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Definition and Usage
The sha1() function calculates the SHA-1 hash of a string.

The sha1() function uses the US Secure Hash Algorithm 1.

From RFC 3174 - The US Secure Hash Algorithm 1: "SHA-1 produces a 160-bit output called a message digest. The message digest can then, for example, be input to a signature algorithm which generates or verifies the signature for the message. Signing the message digest rather than the message often improves the efficiency of the process because the message digest is usually much smaller in size than the message. The same hash algorithm must be used by the verifier of a digital signature as was used by the creator of the digital signature."

This function returns the calculated SHA-1 hash on success, or FALSE on failure.

Syntax
sha1(string,raw)  

Parameter Description
string Required. The string to be calculated
raw Optional. Specify hex or binary output format:
TRUE - Raw 20 character binary format
FALSE - Default. 40 character hex number
Note: This parameter was added in PHP 5.0
 


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Example 1
$str = 'Hello';
echo sha1($str);
?>  

The output of the code above will be:

f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0  


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Example 2
In this example we will print the result of sha1() and then test it:

$str = 'Hello';
echo sha1($str);

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

The output of the code above will be:

f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0
Hello world!