求解16进制字符串的验证的方法:首先使用【hexdec($arr[$i]);】转成10进制相加;然后通过【base_convert((string)$sum,10,16);】转成16进制;最后使用【substr】方法进行求解即可。
如何求解16进制字符串的验证?
问题:
D0 44 00 05 00 09 03 02 00 00 00 00 27 0D
对方告诉后最后的那个27是校验值
算法是求和
求解一段16进制的字符串的验证
因为每个字节是8位,所以求和只要后8位,前面的不要
把27前面的数据相加,然后取后8位
方法:
<?php $string = 'D0 44 00 05 00 09 03 02 00 00 00 00'; $arr = explode(' ',$string); $sum = 0; for($i=0;$i<$len;$i++){ $sum+=hexdec($arr[$i]); //先转成10进制相加 } $sum = base_convert((string)$sum,10,16); //再转成16进制 = 127 //取后面两位 echo substr($sum,-2); // = 27
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