discuz截取字符串是基於php沒有安裝mb_substr等擴展運用的，並且如果截取中文字是二個字符作爲計算。而ecshop是基於php的mb_substr，iconv_substr這兩個擴展來運行的，中文都是以一個字符運算。
discuz 字符串截取
function cutstr($string, $length, $dot = ' ...') {
if(strlen($string) <= $length) {
return $string;
}
$pre = chr(1);
$end = chr(1);
$string = str_replace(array('&', '"', '<', '>'), array($pre.'&'.$end, $pre.'"'.$end, $pre.'<'.$end, $pre.'>'.$end), $string);
$strcut = '';
if(strtolower(CHARSET) == 'utf-8') {
$n = $tn = $noc = 0;
while($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;
}
$strcut = substr($string, 0, $n);
} else {
for($i = 0; $i < $length; $i++) {
$strcut .= ord($string[$i]) > 127 ? $string[$i].$string[++$i] : $string[$i];
}
}
$strcut = str_replace(array($pre.'&'.$end, $pre.'"'.$end, $pre.'<'.$end, $pre.'>'.$end), array('&', '"', '<', '>'), $strcut);
$pos = strrpos($strcut, chr(1));
if($pos !== false) {
$strcut = substr($strcut,0,$pos);
}
return $strcut.$dot;
}
$string = '我是中國人';
echo cutstr($string, 6, $dot = ' ...');//我是中。。。
ecshop 字符串截取
$string = '我是中國人';
echo sub_str($string, 3);//我是中。。。
function sub_str($str, $length = 0, $append = true)
{
$str = trim($str);
$strlength = strlen($str);
if ($length == 0 || $length >= $strlength)
{
return $str;
}
elseif ($length < 0)
{
$length = $strlength + $length;
if ($length < 0)
{
$length = $strlength;
}
}
if (function_exists('mb_substr'))
{
$newstr = mb_substr($str, 0, $length, 'utf-8');
}
elseif (function_exists('iconv_substr'))
{
$newstr = iconv_substr($str, 0, $length, 'utf-8');
}
else
{
//$newstr = trim_right(substr($str, 0, $length));
$newstr = substr($str, 0, $length);
}
if ($append && $str != $newstr)
{
$newstr .= '...';
}
return $newstr;
}