1. Generate random string function
function random($length) {
$hash = '';
$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz';
$max= strlen($ chars) - 1;
mt_srand( (double)microtime() * 1000000);
for($i = 0; $i $hash .= $chars[mt_rand(0, $max)];
}
return $hash;
}
?>
2. Intercept a string of a certain length
Note: This function is valid for GB2312 use
function wordscut($string, $length,$sss=0) {
if (strlen($string) > $length) {
if(ord($string[$i]) > 127) {
$wordscut .= $string[$i].$string[$i + 1];
$i++ ;
} else {
.= $string[$i];
}
}
return $wordscut.$addstr;
}
return $string;
}
?>
3. Obtain the client IP address
function GetIP(){
env("HTTP_CLIENT_IP");
using getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown"))
else if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR") ), "unknown"))
$ip = getenv("REMOTE_ADDR"); mp($_SERVER['REMOTE_ADDR'] , "unknown")) return($ip);
?> = explode('/' . = $temp[$i].'/';
inAddress)
{
return (ereg("^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(.[a-zA-Z0-9_-] )+",$inAddress));
}
?>
6.Jump
function gotourl($message='',$url='',$title='')
{
$html ="
if(!empty($url))
$html .=" $html .="";
$html .="
";
$html .="
"; $html .="
|
$html .="";
echo $html;
exit;
}
?>
7.分页(两个函数配合使用)
function getpage($sql,$page_size=20)
{
global $page,$totalpage,$sums; //out param
$page = $_GET["page"];
//$eachpage = $page_size;
$pagesql = strstr($sql," from ");
$pagesql = "select count(*) as ids ".$pagesql;
$result = mysql_query($pagesql);
if($rs = mysql_fetch_array($result)) $sums = $rs[0];
$totalpage = ceil($sums/$page_size);
if((!$page)||($page $startpos = ($page-1)*$page_size;
$sql .=" limit $startpos,$page_size ";
return $sql;
}
function showbar($string="")
{
global $page,$totalpage;
$out="共".$totalpage."页 ";
$linkNum =4;
$start = ($page-round($linkNum/2))>0 ? ($page-round($linkNum/2)) : "1";
$end = ($page+round($linkNum/2)) $prestart=$start-1;
$nextend=$end+1;
if($page1)
$out .= "第一页 ";
if($start>1)
$out.=".. ";
for($t=$start;$t {
$out .= ($page==$t) ? "[".$t."] " : "$t ";
}
if($end $out.=">>..";
if($page$totalpage)
$out .= " 最后页";
return $out;
}
?>
以上就介绍了https://exo-l.smtown.com/home 一些常用的php函数,包括了https://exo-l.smtown.com/home方面的内容,希望对PHP教程有兴趣的朋友有所帮助。

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Load balancing affects session management, but can be resolved with session replication, session stickiness, and centralized session storage. 1. Session Replication Copy session data between servers. 2. Session stickiness directs user requests to the same server. 3. Centralized session storage uses independent servers such as Redis to store session data to ensure data sharing.

Sessionlockingisatechniqueusedtoensureauser'ssessionremainsexclusivetooneuseratatime.Itiscrucialforpreventingdatacorruptionandsecuritybreachesinmulti-userapplications.Sessionlockingisimplementedusingserver-sidelockingmechanisms,suchasReentrantLockinJ

Alternatives to PHP sessions include Cookies, Token-based Authentication, Database-based Sessions, and Redis/Memcached. 1.Cookies manage sessions by storing data on the client, which is simple but low in security. 2.Token-based Authentication uses tokens to verify users, which is highly secure but requires additional logic. 3.Database-basedSessions stores data in the database, which has good scalability but may affect performance. 4. Redis/Memcached uses distributed cache to improve performance and scalability, but requires additional matching

Sessionhijacking refers to an attacker impersonating a user by obtaining the user's sessionID. Prevention methods include: 1) encrypting communication using HTTPS; 2) verifying the source of the sessionID; 3) using a secure sessionID generation algorithm; 4) regularly updating the sessionID.


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