随机数

/**
 * @随机生成7位数字
 */
function get_number7(){
    $a = range(0,9);
    for($i=0;$i<7;$i++){
        $b[] = array_rand($a);
    }
    $rs=join("",$b);
    return $rs;
}

/**
 * 生成用户的uuid
 * @return string
 */
function get_guid(){
    mt_srand((double)microtime()*10000);
    $charid = strtoupper(md5(uniqid(rand(), true)));
    $hyphen = chr(45);
    $uuid =  substr($charid, 0, 8).$hyphen
        .substr($charid, 8, 4).$hyphen
        .substr($charid,12, 4).$hyphen
        .substr($charid,16, 4).$hyphen
        .substr($charid,20,12) ;
    return strtolower($uuid);
}

/**
+----------------------------------------------------------
 * 生成随机字符串
+----------------------------------------------------------
 * @param int       $length  要生成的随机字符串长度
 * @param string    $type    随机码类型：0，数字+大写字母；1，数字；2，小写字母；3，大写字母；4，特殊字符；-1，数字+大小写字母+特殊字符
+----------------------------------------------------------
 * @return string
+----------------------------------------------------------
 */
function randCode($length = 5, $type = 0) {
    $arr = array(1 => "0123456789", 2 => "abcdefghijklmnopqrstuvwxyz", 3 => "ABCDEFGHIJKLMNOPQRSTUVWXYZ", 4 => "[email protected]#$%^&*(){}[]|");
    $code='';
    if ($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;
}