Day: 2015年12月6日

php 字符串替换常用str_replace函数，但这个函数会对一个字符串进行多次替换，比如

$search  = array('A', 'B', 'C', 'D', 'E');
$replace = array('B', 'C', 'D', 'E', 'F');
$subject = 'A';
echo str_replace($search, $replace, $subject);

php 加密解密小程序，按键盘顺序重新排序字母表

$subject=$_GET['s'];
$replace = ['a'=>'q','b'=>'w','c'=>'e','d'=>'r','e'=>'t','f'=>'y','g'=>'u','h'=>'i','i'=>'o','j'=>'p','k'=>'a', 
 'l'=>'s','m'=>'d','n'=>'f','o'=>'g','p'=>'h','q'=>'j','r'=>'k','s'=>'l','t'=>'z','u'=>'x',
'v'=>'c','w'=>'v','x'=>'b','y'=>'n','z'=>'m'];
$encrypt=strtr($subject, $replace);
$decrypt=strtr($encrypt, array_flip($replace));

echo '加密：'.$encrypt;
echo '解密：'.$decrypt;

//输入abcdefg
//输出 加密：qwertyu解密：abcdefg…