一个改进的UBB类

<？php
/*
如有转载，请注明作者

原作者: 何志强
改进: SonyMusic[ sonymusic@163.net ]
文件: ubb.php
备注: 说是改进，其实核心函数parse（）已经完全重写了，而且思路也是不一样的。
不过仍是受何志强的例子的启发，而且测试的例子还有URLCHECK等几个函数也是沿用的何志强的程序，谢谢何志强。
目前还没有颜色的功能，但我会加入的。
如果在程序上有什么BUG或不便的地方，请给我MAIL。
谢谢！
改进功能:
对字符串进行UBB编码,该类目前只支持下列几个简单且实用的编码:
1. URL裢接
[url] http://phpuser.com/ [/url]
http://头可以不需要
如[url]phpuser.com[/url]也是可以的。
2. Email裢接
[email] sonymusic@163.net [/email]
3. 图片裢接
[img] http://www.phpchina.com/images/logo.gif [/img]
同URL链接一样，前面的http也可以不要。
4. 文字方面
[b]粗体字[/b]
[i]斜体字[/i]
[u]加下划线[/u]
[h1]1号标题字[/h1] ... [h6]6号标题字[/h6]
[sup][/sup]
[sub][/sub]
[tt][/tt]
[s][/s]
[strike][/strike]
[em][/em]
[strong][/strong]
[code][/code]
[samp][/samp]
[kbd][/kbd]
[var][/var]
[dfn][/dfn]
[cite][/cite]
[small][/small]
[big][/big]
[blink][/blink]
注意以下几点:
1. url,email,img等标签是不分大小写的.
2. 在标签中不允许有TAB键出现，但空格允许。
3. 该类要调用htmlencode,htmlencode4textarea,emailcheck函数和urlcheck类.
4. 修改后支持嵌套，但url,email,img这三个标签不是允许嵌套的。
技术资料:
Ultimate Bulletin Board
http://www.ultimatebb.com/
What is UBB Code
http://www.scriptkeeper.com/ubb/ubbcode.html
*/

include（"urlcheck.php"）;
include（"otherfunc.php"）; //这两个文件的内容，附在最后。

//ubbcode类
class ubbcode{
var $call_time=0;
//可处理标签及处理函数对应表
var $tags = array（ //小写的标签 => 对应的处理函数
"url" => "$this->url",
"email" => "$this->email",
"img" => "$this->img",
"b" => "$this->simple",
"i" => "$this->simple",
"u" => "$this->simple",
"tt" => "$this->simple",
"s" => "$this->simple",
"strike" => "$this->simple",
"h1" => "$this->simple",
"h2" => "$this->simple",
"h3" => "$this->simple",
"h4" => "$this->simple",
"h5" => "$this->simple",
"h6" => "$this->simple",
"sup" => "$this->simple",
"sub" => "$this->simple",
"em" => "$this->simple",
"strong" => "$this->simple",
"code" => "$this->simple",
"samp" => "$this->simple",
"kbd" => "$this->simple",
"var" => "$this->simple",
"dfn" => "$this->simple",
"cite" => "$this->simple",
"small" => "$this->simple",
"big" => "$this->simple",
"blink" => "$this->simple"
）;
//url裢接属性
var $attr_url;
//url合法性检查对象
var $urlcheck;

function ubbcode（$attr_url）{
$this->attr_url = "".$attr_url;
$this->urlcheck = new urlcheck（）;
}

//对$str进行UBB编码解析
function parse（$str）{
$this->call_time++;
$parse = "".htmlencode（$str）;

$ret = "";
while（true）{
$eregi_ret=eregi（"[[#]{0,1}[[:alnum:]]{1,7}]",$parse,$eregi_arr）; //查找[xx]
if（！$eregi_ret）{
$ret .= $parse;
break; //如果没有，返回
}
$pos = @strpos （$parse,$eregi_arr[0]）;
$tag_len=strlen（$eregi_arr[0]）-2;//标记长度
$tag_start=substr（$eregi_arr[0],1,$tag_len）;
$tag=strtolower（$tag_start）;

if（（（$tag=="url"） or （$tag=="email"） or （$tag=="img"）） and （$this->call_time>1））{
echo $this->call_time."<br>";
return $parse;//如果不能是不能嵌套的标记，直接返回
}

$parse2 = substr（$parse,0,$pos）;//标记之前
$parse = substr（$parse,$pos+$tag_len+2）;//标记之后
if（！isset（$this->tags[$tag]））{
echo "$tag_start<br>";
$ret .= $parse2."[".$tag_start."]";
continue;//如果是不支持的标记
}

//查找对对应的结束标记
$eregi_ret=eregi（"[/".$tag."]",$parse,$eregi_arr）;
if（！$eregi_ret）{
$ret .= $parse2."[".$tag_start."]";
continue;//如果没有对应该的结束标记
}
$pos=strpos（$parse,$eregi_arr[0]）;
$value=substr（$parse,0,$pos）;//这是起止标记之间的内容
$tag_end=substr（$parse,$pos+2,$tag_len）;
$parse=substr（$parse,$pos+$tag_len+3）;//结束标记之后的内容

if（（$tag！="url"） and （$tag！="email"） and （$tag！="img"））{
$value=$this->parse（$value）;
}

$ret .= $parse2;
eval（"$ret .= ".$this->tags[$tag]."（"".$tag_start."","".$tag_end."","".$value.""）;"）;
}
$this->call_time--;
return $ret;
}

function simple（$start,$end,$value）{
return "<".$start.">".$value."</".$end.">";
}

function url（$start,$end,$value）{
$trim_value=trim（$value）;
if （strtolower（substr（$trim_value,0,7））！="http://"）
$trim_value="http://".$trim_value;
if（$this->urlcheck->check（$trim_value）） return "<a href="".$trim_value."" ".$this->attr_url.">".$value."</a>";
else return "[".$start."]".$value."[/".$end."]";
}

function email（$start,$end,$value）{
if（emailcheck（$value）） return "<a href="mailto:".$value."">".$value."</a>";
else return "[".$start."]".$value."[/".$end."]";
}

function img（$start,$end,$value）{
$trim_value=trim（$value）;
if （（strtolower（substr（$trim_value,0,7））！="http://"） or （$this->urlcheck->check（$trim_value）））
return "<img src="".$trim_value.""></img>";
else return "[".$start."]".$value."[/".$end."]";
}
}

//测试
echo "<html>";
echo "<head><title>测试</title></head>";
echo "<body>";
echo "<form action="".str2url（$PATH_INFO）."" method="post">";
echo "<textarea cols="100" rows="10" name="ubb">".htmlencode4textarea（$ubb）."</textarea><br>";
echo "<input type="submit" value="转换">";
echo "</form>";

if（isset（$ubb））{
$ubbcode = new ubbcode（"target="_blank""）;
echo "<hr>".$ubbcode->parse（$ubb）;
}

echo "</body>";
echo "</html>";

？>

文件urlcheck.php的内容：
<？php
//urlcheck.php
class urlcheck{
var $regex = array（//协议名（注意在这里必须写成小写） => 对应的正则表达式
"ftp" => "$this->ftpurl",
"file" => "$this->fileurl",
"http" => "$this->httpurl",
"https" => "$this->httpurl",
"gopher" => "$this->gopherurl",
"news" => "$this->newsurl",
"nntp" => "$this->nntpurl",
"telnet" => "$this->telneturl",
"wais" => "$this->waisurl"
）;

var $lowalpha;
var $hialpha;
var $alpha;
var $digit;
var $safe;
var $extra;
var $national;
var $punctuation;
var $reserved;
var $hex;
var $escape;
var $unreserved;
var $uchar;
var $xchar;
var $digits;

var $urlpath;
var $password;
var $user;
var $port;
var $hostnumber;
var $alphadigit;
var $toplabel;
var $domainlabel;
var $hostname;
var $host;
var $hostport;
var $login;

//ftp
var $ftptype;
var $fsegment;
var $fpath;
var $ftpurl;

//file
var $fileurl;

//http,https
var $search;
var $hsegment;
var $hpath;
var $httpurl;

//gopher
var $gopher_string;
var $selector;
var $gtype;
var $gopherurl;

//news
var $article;
var $group;
var $grouppart;
var $newsurl;

//nntp
var $nntpurl;

//telnet
var $telneturl;

//wais
var $wpath;
var $wtype;
var $database;
var $waisdoc;
var $waisindex;
var $waisdatabase;
var $waisurl;

function check（$url）{
$pos = @strpos （$url,":",1）;
if（$pos<1） return false;
$prot = substr（$url,0,$pos）;
if（！isset（$this->regex[$prot]）） return false;
eval（"$regex = ".$this->regex[$prot].";"）;
return ereg（"^".$regex."$",$url）;
}

function urlcheck（）{
$this->lowalpha = "[a-z]";
$this->hialpha = "[A-Z]";
$this->alpha = "（".$this->lowalpha."|".$this->hialpha."）";
$this->digit = "[0-9]";
$this->safe = "[$.+_-]";
$this->extra = "[*（）"！,]";
$this->national = "（[{}|^~`]|[|]）";
$this->punctuation = "[<>#%"]";
$this->reserved = "[？;/: @&= ]";
$this->hex = "（".$this->digit."|[a-fA-F]）";
$this->escape = "（%".$this->hex."{2}）";
$this->unreserved = "（".$this->alpha."|".$this->digit."|".$this->safe."|".$this->extra."）";
$this->uchar = "（".$this->unreserved."|".$this->escape."）";
$this->xchar = "（".$this->unreserved."|".$this->reserved."|".$this->escape."）";
$this->digits = "（".$this->digit."+）";

$this->urlpath = "（".$this->xchar."*）";
$this->password = "（（".$this->uchar."|[？;&=]"."）*）";
$this->user = "（（".$this->uchar."|[？;&=]"."）*）";
$this->port = $this->digits;
$this->hostnumber = "（".$this->digits.".".$this->digits.".".$this->digits.".".$this->digits."）";
$this->alphadigit = "（".$this->alpha."|".$this->digit."）";
$this->toplabel = "（".$this->alpha."|（".$this->alpha."（".$this->alphadigit."|-）*".$this->alphadigit."））";
$this->domainlabel = "（".$this->alphadigit."|（".$this->alphadigit."（".$this->alphadigit."|-）*".$this->alphadigit."））";
$this->hostname = "（（".$this->domainlabel.".）*".$this->toplabel."）";
$this->host = "（".$this->hostname."|".$this->hostnumber."）";
$this->hostport = "（".$this->host."（:".$this->port."）？）";
$this->login = "（（".$this->user."（:".$this->password."）？@）？".$this->hostport."）";

$this->ftptype = "[aidAID]";
$this->fsegment = "（（".$this->uchar."|[？: @&= ]）*）";
$this->fpath = "（".$this->fsegment."（/".$this->fsegment."）*）";
$this->ftpurl = "（[fF][tT][pP]://".$this->login."（/".$this->fpath."（;[tT][yY][pP][eE]=".$this->ftptype."）？）？）";

$this->fileurl = "（[fF][iI][lL][eE]://（".$this->host."|[lL][oO][cC][aA][lL][hH][oO][sS][tT]）？/".$this->fpath."）";

$this->search = "（（".$this->uchar."|[;: @&= ]）*）";
$this->hsegment = "（（".$this->uchar."|[;: @&= ]）*）";
$this->hpath = "（".$this->hsegment."（/".$this->hsegment."）*）";
$this->httpurl = "（[hH][tT][tT][pP][sS]？://".$this->hostport."（/".$this->hpath."（[？]".$this->search."）？）？）";

$this->gopher_string = "（".$this->xchar."*）";
$this->selector = "（".$this->xchar."*）";
$this->gtype = $this->xchar;
$this->gopherurl = "（[gG][oO][pP][hH][eE][rR]://".$this->hostport."（/（".$this->gtype."（".$this->selector."（%09".$this->search."（%09".$this->gopher_string."）？）？）？）？）？）";

$this->article = "（（".$this->uchar."|[;/？:&=]） +@".$this- >host."）";
$this->group = "（".$this->alpha."（".$this->alpha."|".$this->digit."|[-.+_]）*）";
$this->grouppart = "（[*]|".$this->group."|".$this->article."）";
$this->newsurl = "（[nN][eE][wW][sS]:".$this->grouppart."）";

$this->nntpurl = "（[nN][nN][tT][pP]://".$this->hostport."/".$this->group."（/".$this->digits."）？）";

$this->telneturl = "（[tT][eE][lL][nN][eE][tT]://".$this->login."/？）";

$this->wpath = "（".$this->uchar."*）";
$this->wtype = "（".$this->uchar."*）";
$this->database = "（".$this->uchar."*）";
$this->waisdoc = "（[wW][aA][iI][sS]://".$this->hostport."/".$this->database."/".$this->wtype."/".$this->wpath."）";
$this->waisindex = "（[wW][aA][iI][sS]://".$this->hostport."/".$this->database."[？]"$this->search."）";
$this->waisdatabase = "（[wW][aA][iI][sS]://".$this->hostport."/".$this->database."）";
$this->waisurl = "（".$this->waisdatabase."|".$this->waisindex."|".$this->waisdoc."）";
}
}

？>

文件otherfunc.php的内容：
<？php
//otherfunc.php
function htmlencode（$str）{
$str = （string）$str;

$ret = "";
$len = strlen（$str）;
$nl = false;
for（$i=0;$i<$len;$i++）{
$chr = $str[$i];
switch（$chr）{
case "<":
$ret .= "<";
$nl = false;
break;
case ">":
$ret .= ">";
$nl = false;
break;
case """:
$ret .= """;
$nl = false;
break;
case "&":
$ret .= "&";
$nl = false;
break;
/*
case " ":
$ret .= " ";
$nl = false;
break;
*/
case chr（9）:
$ret .= "    ";
$nl = false;
break;
case chr（10）:
if（$nl） $nl = false;
else{
$ret .= "<br>";
$nl = true;
}
break;
case chr（13）:
if（$nl） $nl = false;
else{
$ret .= "<br>";
$nl = true;
}
break;
default:
$ret .= $chr;
$nl = false;
break;
}
}

return $ret;
}

function htmlencode4textarea（$str）{
$str = （string）$str;

$ret = "";
$len = strlen（$str）;
for（$i=0;$i<$len;$i++）{
$chr = $str[$i];
switch（$chr）{
case "<":
$ret .= "<";
break;
case ">":
$ret .= ">";
break;
case """:
$ret .= """;
break;
case "&":
$ret .= "&";
break;
case " ":
$ret .= " ";
break;
case chr（9）:
$ret .= "    ";
break;
default:
$ret .= $chr;
break;
}
}

return $ret;
}

function emailcheck（$email）{
$ret=false;
if（strstr（$email, "@" ） && strstr（$email, "."））{
if（eregi（"^（[_a-z0-9]+（[._a-z0-9-]+）*）@（[a-z0-9]{2,}（.[a-z0-9-]{2,}）*.[a-z]{2,3}）$", $email））{
$ret=true;
}
}
return $ret;
}

function str2url（$path）{
return eregi_replace（"%2f","/",urlencode（$path））;
}
？>