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>crc32</H1
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> (PHP 4 >= 4.0.1, PHP 5)</P
>crc32 -- Calcula polinômio crc32 de uma string</DIV
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><H2
>Descrição</H2
>int <B
CLASS="methodname"
>crc32</B
> ( string str )<BR
></BR
><P
> Gera o polinômio cyclic redundancy checksum de 32-bit
de comprimento do <CODE
CLASS="parameter"
>str</CODE
>. É usado geralmente
para validar a integridade de um dado sendo transferido.
</P
><P
> Devido ao tipo integer do PHP conter sinal e muitos dos checksums crc32
resultarem em integers negativos, você precisa usar o formatador "%u"
de <A
HREF="function.sprintf.html"
><B
CLASS="function"
>sprintf()</B
></A
> ou <A
HREF="function.printf.html"
><B
CLASS="function"
>printf()</B
></A
> para obter
uma string representando o checksum crc32 sem sinal.
</P
><P
> Este segundo exemplo mostra com exibir um checksum convertido com a função
<A
HREF="function.printf.html"
><B
CLASS="function"
>printf()</B
></A
>:
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>Exemplo 1. Mostrando um checksum crc32</B
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><code><font color="#000000">
<font color="#0000BB"><?php<br />$checksum </font><font color="#007700">= </font><font color="#0000BB">crc32</font><font color="#007700">(</font><font color="#DD0000">"The quick brown fox jumped over the lazy dog."</font><font color="#007700">); <br /></font><font color="#0000BB">printf</font><font color="#007700">(</font><font color="#DD0000">"%u\n"</font><font color="#007700">, </font><font color="#0000BB">$checksum</font><font color="#007700">);<br /></font><font color="#0000BB">?></font>
</font>
</code></TD
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</P
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> Veja também <A
HREF="function.md5.html"
><B
CLASS="function"
>md5()</B
></A
> e <A
HREF="function.sha1.html"
><B
CLASS="function"
>sha1()</B
></A
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