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1. Generate random string function
function random($length) {
$hash = '';
$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz';
$ max = strlen($chars) - 1;
mt_srand((double)microtime() * 1000000);
for($i = 0; $i < $length; $i++) {
$ hash .= $chars[mt_rand(0, $max)];
}
return $hash;
}
?>
2. Intercept a string of a certain length
Note: This function is valid for GB2312
function wordscut($string, $length,$sss=0) {
if(strlen($string) > $length) {
if($sss){
$length=$length - 3;
$addstr= '...';
for($i = 0; $i < $length; $i++) {
if(ord($string[$i]) > 127) {
$wordscut .= $string[ $i].$string[$i + 1];
$i++;
} else {
$wordscut .= $string[$i];
}
}
return $wordscut.$addstr;
}
return $string;
}
?>
3. Get the client IP address
function GetIP(){
if (getenv("HTTP_CLIENT_IP") && strcasecmp(getenv("HTTP_CLIENT_IP"), "unknown"))
$ip = getenv("HTTP_CLIENT_IP");
else if (getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown"))
$ip = getenv("HTTP_X_FORWARDED_FOR");
else if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR"), "unknown"))
$ip = getenv("REMOTE_ADDR"); _SERVER['REMOTE_ADDR ']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], "unknown"))
$ip = $_SERVER['REMOTE_ADDR'];
else
$ip = "unknown";
return($ip);
}
?>
4. Create the corresponding folder
function createdir($dir='')
{
if (!is_dir($dir))
{
$temp = explode('/',$dir);
$cur_dir = '';
for($i= 0;$i
?>
5. Determine the email address
function checkEmail($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 .=" table>"; ";
$html .="";
$html .="< tr class='m_title'>";
$html .="".$title." ";
$html .="< tr class='line_1'>";
$html .="
".$message."
if (!empty($url))
$html .="The system will return in 3 seconds
If your browser cannot return automatically, please click [Here]Enter";
else
$html .="[Return]";
$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<1)) $page=1;
$startpos = ($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($linkNum/2))<$totalpage ? ($page+round($linkNum/2)) : $totalpage;
$prestart=$start-1;
$nextend=$end+1;
if($page<>1)
$out .= "第一页 ";
if($start>1)
$out.="..<< ";
for($t=$start;$t<=$end;$t++)
{
$out .= ($page==$t) ? "[".$t."] " : "$t ";
}
if($end<$totalpage)
$out.=">>..";
if($page<>$totalpage)
$out .= " 最后页";
return $out;
}
?>
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