PHP 获取字符串 函数

//获取字符串
function getstr($string, $length, $in_slashes=0, $out_slashes=0, $censor=0, $bbcode=0, $html=0) {
global $_SC, $_SGLOBAL;

$string = trim($string);

if($in_slashes) {
//传入的字符有slashes
$string = sstripslashes($string);
}
if($html < 0) {
//去掉html标签
$string = preg_replace("/(/<[^/<]*/>|/r|/n|/s|/[.+?/])/is", ' ', $string);
$string = shtmlspecialchars($string);
} elseif ($html == 0) {
//转换html标签
$string = shtmlspecialchars($string);
}
if($censor) {
//词语屏蔽
@include_once(S_ROOT.'./data/data_censor.php');
if($_SGLOBAL['censor']['banned'] && preg_match($_SGLOBAL['censor']['banned'], $string)) {
showmessage('information_contains_the_shielding_text');
} else {
$string = empty($_SGLOBAL['censor']['filter']) ? $string :
@preg_replace($_SGLOBAL['censor']['filter']['find'], $_SGLOBAL['censor']['filter']['replace'], $string);
}
}
if($length && strlen($string) > $length) {
//截断字符
$wordscut = '';
if(strtolower($_SC['charset']) == 'utf-8') {
//utf8编码
$n = 0;
$tn = 0;
$noc = 0;
while ($n < strlen($string)) {
$t = ord($string[$n]);
if($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) {
$tn = 1;
$n++;
$noc++;
} elseif(194 <= $t && $t <= 223) {
$tn = 2;
$n += 2;
$noc += 2;
} elseif(224 <= $t && $t < 239) {
$tn = 3;
$n += 3;
$noc += 2;
} elseif(240 <= $t && $t <= 247) {
$tn = 4;
$n += 4;
$noc += 2;
} elseif(248 <= $t && $t <= 251) {
$tn = 5;
$n += 5;
$noc += 2;
} elseif($t == 252 || $t == 253) {
$tn = 6;
$n += 6;
$noc += 2;
} else {
$n++;
}
if ($noc >= $length) {
break;
}
}
if ($noc > $length) {
$n -= $tn;
}
$wordscut = substr($string, 0, $n);
} else {
for($i = 0; $i < $length - 1; $i++) {
if(ord($string[$i]) > 127) {
$wordscut .= $string[$i].$string[$i + 1];
$i++;
} else {
$wordscut .= $string[$i];
}
}
}
$string = $wordscut;
}
if($bbcode) {
include_once(S_ROOT.'./source/function_bbcode.php');
$string = bbcode($string, $bbcode);
}
if($out_slashes) {
$string = saddslashes($string);
}
return trim($string);
}