php实现java的byte数组转换
由于工作需要,自己写的一个php实现java的byte数组转换的类。
/**
?* byte数组与字符串转化类
?* @author zikie
?* Created on 2011-7-15
?*/
class Bytes {
???
??? /**
???? * 转换一个String字符串为byte数组
???? * @param $str 需要转换的字符串
???? * @param $bytes 目标byte数组
???? * @author Zikie
???? */
????
??? public static function getBytes($str) {
??? ??? $len = strlen($str);
??? ??? $bytes = array();
?? ??? ??? for($i=0;$i?? ??? ??? ??? if(ord($str[$i]) >= 128){
?? ??? ??? ??? ??? $byte = ord($str[$i]) - 256;
?? ??? ??? ??? }else{
?? ??? ??? ??? ??? $byte = ord($str[$i]);
?? ??? ??? ??? }
??????? ??? $bytes[] =? $byte ;
??? ??? }
??? ??? return $bytes;
??? }
???
??? /**
???? * 将字节数组转化为String类型的数据
???? * @param $bytes 字节数组
???? * @param $str 目标字符串
???? * @return 一个String类型的数据
???? */
????
??? public static function toStr($bytes) {
??? ??? $str = '';
??? ??? foreach($bytes as $ch) {
??????? ??? $str .= chr($ch);
??? ??? }
?? ??? ??? return $str;
??? }
???
??? /**
???? * 转换一个int为byte数组
???? * @param $byt 目标byte数组
???? * @param $val 需要转换的字符串
???? * @author Zikie
???? */
???
??? public static function integerToBytes($val) {
??? ??? $byt = array();
??? ??? $byt[0] = ($val & 0xff);
??? ??? $byt[1] = ($val >> 8 & 0xff);
??? ??? $byt[2] = ($val >> 16 & 0xff);
??????? $byt[3] = ($val >> 24 & 0xff);
??????? return $byt;
??? }
???
??? /**
???? * 从字节数组中指定的位置读取一个Integer类型的数据
???? * @param $bytes 字节数组
???? * @param $position 指定的开始位置
???? * @return 一个Integer类型的数据
???? */
????
??? public static function bytesToInteger($bytes, $position) {
??????? $val = 0;
??????? $val = $bytes[$position + 3] & 0xff;
??????? $val ??????? $val |= $bytes[$position + 2] & 0xff;
??????? $val ??????? $val |= $bytes[$position + 1] & 0xff;
??????? $val ??????? $val |= $bytes[$position] & 0xff;
??????? return $val;
??? }
??? /**
???? * 转换一个shor字符串为byte数组
???? * @param $byt 目标byte数组
???? * @param $val 需要转换的字符串
???? * @author Zikie
???? */
???
??? public static function shortToBytes($val) {
??? ??? $byt = array();
??? ??? $byt[0] = ($val & 0xff);
??????? $byt[1] = ($val >> 8 & 0xff);
??????? return $byt;
??? }
???
??? /**
???? * 从字节数组中指定的位置读取一个Short类型的数据。
???? * @param $bytes 字节数组
???? * @param $position 指定的开始位置
???? * @return 一个Short类型的数据
???? */
????
??? public static function bytesToShort($bytes, $position) {
??????? $val = 0;
??????? $val = $bytes[$position + 1] & 0xFF;
??????? $val = $val ??????? $val |= $bytes[$position] & 0xFF;
??????? return $val;
??? }
???
}
?>

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