• JavaScript默认32位，32位操作系统int类型的最大值是 2147483647，超过该数值会溢出
  • php 64位需要使用pack转化

PHP中pack、unpack的详细用法：

  • JavaScript运行结果
php和js位移运算的坑
php和js位移运算的坑
  • PHP运行结果
php和js位移运算的坑
php和js位移运算的坑

JavaScript

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function (t) hash33{
    for (var e = 0, i = 0, n = t . length; i < n; ++i)
        e += (e << 5) + t . charCodeAt(i);
        return 2147483647 & e
}

PHP

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function hash33($t){
    for ( $e = 0, $i = 0, $n = strlen($t); $i < $n; ++$i){
        $tmp = $e << 5;
        $tmp = unpack("L",pack("L",$tmp))[1];
        $e += $tmp+  uniord(mb_substr($t,$i,1,'utf-8'));
    }
    return 2147483647 & $e;
}