// 随机字符串 function random($length, $numeric = FALSE) { $seed = base_convert(md5(microtime() . $_SERVER['DOCUMENT_ROOT']), 16, $numeric ? 10 : 35); $seed = $numeric ? (str_replace('0', '', $seed) . '012340567890') : ($seed . 'zZ' . strtoupper($seed)); if ($numeric) { $hash = ''; } else { $hash = chr(rand(1, 26) + rand(0, 1) * 32 + 64); $length--; } $max = strlen($seed) - 1; for ($i = 0; $i < $length; $i++) { $hash .= $seed{mt_rand(0, $max)}; } return $hash; } // 单位转化 function sizecount($size) { if($size >= 1073741824) { $size = round($size / 1073741824 * 100) / 100 . ' GB'; } elseif($size >= 1048576) { $size = round($size / 1048576 * 100) / 100 . ' MB'; } elseif($size >= 1024) { $size = round($size / 1024 * 100) / 100 . ' KB'; } else { $size = $size . ' Bytes'; } return $size; }