本文出至：新太潮流网络博客
/** * [生成随机字符串] * @E-mial wuliqiang_aa@163.com * @TIME ??2017-04-07 * @WEB ???http://blog.iinu.com.cn * @param ?integer $length [生成的长度] * @param ?integer $type ??[生成的类型] * @return [type] ??str ??????[description] * @php 随机码类型：0，数字+大写字母；1，数字；2，小写字母；3，大写字母；4，特殊字符；-1，数字+大小写字母+特殊字符 */function randCode($length = 5, $type = 0) { ???$arr = array(1 => "0123456789", 2 => "abcdefghijklmnopqrstuvwxyz", 3 => "ABCDEFGHIJKLMNOPQRSTUVWXYZ", 4 => "~@#$%^&*(){}[]|"); ???if ($type == 0) { ???????array_pop($arr); ???????$string = implode("", $arr); ???} else if ($type == "-1") { ???????$string = implode("", $arr); ???} else { ???????$string = $arr[$type]; ???} ???$count = strlen($string) - 1; ???for ($i = 0; $i < $length; $i++) { ???????$str[$i] = $string[rand(0, $count)]; ???????$code .= $str[$i]; ???} ???return $code;}/** * [生成唯一字符串] * @E-mial wuliqiang_aa@163.com * @TIME ??2017-04-07 * @WEB ???http://blog.iinu.com.cn * @ 0-存数字字符串；1-小写字母字符串；2-大写字母字符串；3-大小写数字字符串；4-字符； * ??5-数字，小写，大写，字符混合 * @param ?integer $type ??[字符串的类型] * @param ?integer $length [字符串的长度] * @param ?integer $time ??[是否带时间1-带，0-不带] * @return [string] ?$str ???[返回唯一字符串] */function randSole($type = 0,$length = 18,$time=0){ ???$str = $time == 0 ? ‘‘:date(‘YmdHis‘,time()); ???switch ($type) { ???????case 0: ???????????for((int)$i = 0;$i <= $length;$i++){ ???????????????if(mb_strlen($str) == $length){ ???????????????????$str = $str; ???????????????}else{ ???????????????????$str .= rand(0,9); ???????????????} ???????????} ???????????break; ???????case 1: ???????????for((int)$i = 0;$i <= $length;$i++){ ???????????????if(mb_strlen($str) == $length){ ???????????????????$str = $str; ???????????????}else{ ???????????????????$rand = "qwertyuioplkjhgfdsazxcvbnm"; ???????????????????$str .= $rand{mt_rand(0,26)}; ???????????????} ???????????} ???????????break; ???????case 2: ???????????for((int)$i = 0;$i <= $length;$i++){ ???????????????if(mb_strlen($str) == $length){ ???????????????????$str = $str; ???????????????}else{ ???????????????????$rand = "QWERTYUIOPLKJHGFDSAZXCVBNM"; ???????????????????$str .= $rand{mt_rand(0,26)}; ???????????????} ???????????} ???????????break; ???????case 3: ???????????for((int)$i = 0;$i <= $length;$i++){ ???????????????if(mb_strlen($str) == $length){ ???????????????????$str = $str; ???????????????}else{ ???????????????????$rand = "123456789qwertyuioplkjhgfdsazxcvbnmQWERTYUIOPLKJHGFDSAZXCVBNM"; ???????????????????$str .= $rand{mt_rand(0,35)}; ???????????????} ???????????} ???????????break; ???????case 4: ???????????for((int)$i = 0;$i <= $length;$i++){ ???????????????if(mb_strlen($str) == $length){ ???????????????????$str = $str; ???????????????}else{ ???????????????????$rand = "!@#$%^&*()_+=-~`"; ???????????????????$str .= $rand{mt_rand(0,17)}; ???????????????} ???????????} ???????????break;case5:for((int)$i =0;$i <= $length;$i++){if(mb_strlen($str)== $length){ ???????????????????$str = $str;}else{ ???????????????????$rand ="123456789qwertyuioplkjhgfdsazxcvbnmQWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_+=-~`"; ???????????????????$str .= $rand{mt_rand(0,52)};}}break;}return $str;}本文出至：新太潮流网络博客
PHP生成随机或者唯一字符串
原文地址：http://www.cnblogs.com/disoq/p/7509163.html