能向我解释有人在PHP中包（）函数？ [英] Can someone explain to me the pack() function in PHP?

问题描述

我想知道更多关于PHP包（）函数：<一href=\"http://fi.php.net/manual/en/function.pack.php\">http://fi.php.net/manual/en/function.pack.php

I would like to know more about the pack() function in PHP: http://fi.php.net/manual/en/function.pack.php

我知道它的数据打包成二进制，但我不知道那些v为V NñC C的意思是，我想知道如果有人能善待并给我一个实际演示时使用的格式？

I know it packs data into binary, but I'm not sure what all those v V n N c C mean and I was wondering if someone could be kind and give me a practical demonstration when to use which formats?

在线文档，变更，缺乏信息，在我看来。

The online documentation, for change, lacks of information, in my opinion.

推荐答案

这些重present你想怎么你正在收拾的数据进行重新二进制格式psented $ P $：

Those represent how you want the data you are packing to be represented in binary format:

所以

$斌=包（V，1）; = GT; 0000000000000001 （16位）

其中，

$斌=包（V，1）=＆GT; 00000000000000000000000000000001 （32位）

它告诉收拾你想怎么在二进制数据psented数据重新$ P $。
下面的code将证明这一点。请注意，您可以使用不同的解压
从你挤满了数据的格式。

It tells pack how you want the data represented in the binary data. The code below will demonstrate this. Note that you can unpack with a different format from what you packed the data as.

<?php

$bin = pack("S", 65535);
$ray = unpack("S", $bin);
echo "UNSIGNED SHORT VAL = ", $ray[1], "\n";

$bin = pack("S", 65536);
$ray = unpack("S", $bin);
echo "OVERFLOW USHORT VAL = ", $ray[1], "\n";

$bin = pack("V", 65536);
$ray = unpack("V", $bin);
echo "SAME AS ABOVE BUT WITH ULONG VAL = ", $ray[1], "\n";
?>

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