php模拟js函数unescape的函数代码

复制代码 代码如下:

  function unescape($str)

  {

  $ret = '';

  $len = strlen($str);

  for ($i = 0; $i < $len; $i++)

  {

  if ($str[$i] == '%' && $str[$i+1] == 'u')

  {

  $val = hexdec(substr($str, $i+2, 4));

  if ($val < 0x7f) $ret .= chr($val);

  else if($val < 0x800) $ret .= chr(0xc0|($val>>6)).chr(0x80|($val&0x3f));

  else $ret .= chr(0xe0|($val>>12)).chr(0x80|(($val>>6)&0x3f)).chr(0x80|($val&0x3f));

  $i += 5;

  }

  else if ($str[$i] == '%')

  {

  $ret .= urldecode(substr($str, $i, 3));

  $i += 2;

  }

  else $ret .= $str[$i];

  }

  return $ret;

  }