php怎么实现转成byte数组

本文操作环境：windows7系统、PHP7.1版、DELL G3电脑

php怎么实现转成byte数组？

php转换byte[]数据类型

代码如下：

<?php
class Bytes {
    
    public static function getbytes($str) {
        $len = strlen($str);
        $bytes = array();
        for($i=0;$i<$len;$i++) {
            if(ord($str[$i]) >= 128){
                $byte = ord($str[$i]) - 256;
            }else{
                $byte = ord($str[$i]);
            }
            $bytes[] =  $byte ;
        }
        return $bytes;
    }
 
    
    public static function tostr($bytes) {
        $str = '';
        foreach($bytes as $ch) {
            $str .= chr($ch);
        }
        return $str;
    }
 
    
    public static function integertobytes($val) {
        $byt = array();
        $byt[0] = ($val & 0xff);
        $byt[1] = ($val >> 8 & 0xff);
        $byt[2] = ($val >> 16 & 0xff);
        $byt[3] = ($val >> 24 & 0xff);
        return $byt;
    }
 
    
    public static function bytestointeger($bytes, $position) {
        $val = 0;
        $val = $bytes[$position + 3] & 0xff;
        $val <<= 8;
        $val |= $bytes[$position + 2] & 0xff;
        $val <<= 8;
        $val |= $bytes[$position + 1] & 0xff;
        $val <<= 8;
        $val |= $bytes[$position] & 0xff;
        return $val;
    }
 
    
    public static function shorttobytes($val) {
        $byt = array();
        $byt[0] = ($val & 0xff);
        $byt[1] = ($val >> 8 & 0xff);
        return $byt;
    }
 
    
    public static function bytestoshort($bytes, $position) {
        $val = 0;
        $val = $bytes[$position + 1] & 0xff;
        $val = $val << 8;
        $val |= $bytes[$position] & 0xff;
        return $val;
    }
}