PHP crc32 () function
Examples
Output crc32 () result:
$str = crc32("Hello World!");
printf("%un",$str);
?>
Running instance »
Definition and Usage
crc32 () function calculates a string of 32-bit CRC (cyclic redundancy check).
This function can be used to verify data integrity.
Tip: To make sure you from crc32 () function to obtain the correct string representation, you must use the printf () or sprintf () function% u format character.If you do not use the% u format character, the results may appear to be incorrect or negative numbers.
grammar
| 参数 | 描述 |
|---|---|
| string | 必需。规定要计算的字符串。 |
technical details
| return value: | Returned as an integer string of 32-bit cyclic redundancy check code polynomial. |
|---|---|
| PHP version: | 4.0.1+ |
Example 1
In this example, we will use and without the use of "% u" formatter, the output crc32 () results (Note that the results are the same):
$str = crc32("Hello world!");
echo 'Without %u: '.$str."<br>";
echo 'With %u: ';
printf("%u",$str);
?>
The code above will output:
With %u: 461707669
Example 2
In this example, we will use and without the use of "% u" formatter, the output crc32 () results (Note that the results are not the same):
$str = crc32("Hello world.");
echo 'Without %u: '.$str."<br>";
echo 'With %u: ';
printf("%u",$str);
?>
The code above will output:
With %u: 2335835140
PHP String Reference