也许你还在将HTML代码和PHP代码混着一起写，也许你还不知道什么叫模板类。
那么请你仔细看看这篇文章。我站在过来人的角度告诉你，花时间看这篇文章不
会错的。
真正看了，学了这篇文章后，相信你应该做自己的网站了。
那么让我们开始吧。
第一章 如何进行安装配置
PHP世界中比较流行的模板处理工具有PHPLIB Template和FastTemplate两种。据笔者看有关资料介绍，PHPLIB Template的技术易用性和速度较为理想，所以俺就学习使用了PHPLIB Template。
phplib template 的安装其实非常简单。现在说简单，呵呵，其实刚开始上手的时候竟然花了好几天的功夫才知道大概是怎么一回事儿。那我们首先来认识一下phplib吧。
随着php的应用和推广，众多开发人员和很多爱好者在php的基础上开发了很多php的程序库，这些程序库大大简化了程序设计和提高了代码的可重用性。其中phplib就是这些库中相当优秀的产品。phplib有五大功能：将数据库驱动和对数据库操作完全分离；支持session；权限许可；模板；购物车。我们要用的模板功能只是phplib这个库的诸多功能中的一种。笔者刚开始看phplib 的网方官站，就看得一头雾水，怎么还有数据库、session等等，最后才明白原来俺需要的只是template。
要说安装，其实就是下载phplib库文件。你可以到phplib的官方网站下载最新的版本：
http://phplib.sourceforge.net 这是一个 tar.gz 压缩包，下载完之后就是解压了。打开解压后的文件夹，里边有一个php文件夹，将该php文件夹复制到任何你想要的其它位置，但不要放在网页服务器的目录下。比如：我的网页服务器根目录是：/var/www，我可以将php文件夹放在/ var下，与www文件夹平行。然后打开php的配置文件php.ini进行编辑。更改include_path,使其指向刚刚复制的php文件夹的位置。比如：include_path = “.:/var/www/php”。phplib的官方站quick guide to installation讲了十个步骤，我们只用phplib template这一项功能的话，其它的安装步骤其实根本不用理会。保存退出，重启 apache2服务。然后就可以尝试编写你的第一个模板页了。
第二章 第一个简单的模板页
我理解，所谓”模板”，就是将界面和实现代码分离开来，这样做的目的一是将美工和程序员的工作分离开来，提高工作效率，二是方便维护。下面我们就开始尝试写一个简单的模板了，文件名first.htm。
< HTML>
< HEAD>
< TITLE> 我的第一个模板文件 < /TITLE>
< /HEAD>
< BODY>
你知道吗？ {man}真是一个好人。
< font color=”#0000FF”> 作者：{author}</font>
< /BODY>
< /HTML>
first.html模板中的{man}{author}{date}可以称为”模板变量”，用花括号({})括起来。
上面我们定义三个变量的原因是我们想随时改变它们的值，下面我们就来做这个工作。新建first.php文件，内容如下:
<?php
include (’template.inc’); //包含进模板类 template.inc
$tpl = new Template; //创建一个新模板
$tpl->set_file(’main’, ‘first.html’); //把模板文件加载进来
$tpl->set_var(’man’, ‘fuyatao’); // //给文件中的模板变量赋值
$tpl->set_var(’author’, ‘fuyatao’);
$tpl->parse(’mains’, ‘main’); // //完成替换
$tpl->p(’mains’); // //输出替换的结果
?>
你也可以一次完成给变量赋值，这样
$tpl->set_var(
array(’man’=>’fuyatao’, ‘author’=>’fuyatao’)
);
浏览器中浏览这个文件,你就会发现输出：你知道吗？fuyatao真是一个好人。作者：fuyatao.
初次尝试还算顺利吧？如果没有如你所愿地看到上述文字，那一定是你哪里弄错了。浏览器会有提示。还有如果你将这些代码复制到本机不能正确执行，有可能是标点符号的问题，必须用英文的标点符号，程序中用中文的引号或分号都会引起程序不能正常运行，本人就曾经吃过这个亏，反复检查程序没有错，可就是执行不了，后来才发现是一个地方用错了标点。
第三章 稍复杂点的应用
现在我们设想稍微复杂一点的情况，新建一个second.htm模板文件，内容为：
<HTML>
<HEAD>
<TITLE>第二个模板文件</TITLE>
</HEAD> <BODY>
下面是一个列表
<UL>
<li>谷军涛 的身高是 170cm
<li>武剑 的身高是 171cm
<li>青竹 的身高是 180cm
<li>王聪聪 的身高是 172cm
</UL>
</BODY>
</HTML>
以上页面是纯静态的，假设要使用数据库，用PHP代码嵌入HTML的话，是这样写的:
<HTML>
<HEAD>
<TITLE>第二个模板文件</TITLE>
</HEAD> <BODY>
下面是一个列表
<?php
$link=mysql_connect(’localhost’,'fuyatao’,’ passwd’);
$result=mysql_db_query(’gfs’,’select name,tall from my_table’);
echo “<UL>”;
while ($a = mysql_fetch_array($result)){
echo “<li>$a[name]的身高是$a[tall]”;
}
?>
</UL>
</BODY>
</HTML>
PHP新手一般都这样写，但你很快发现：你或者美工改这个列表样式的时候需要多么的小心翼翼,特别是美工，如果他不懂PHP代码，那么他会终日在恐惧之中！因为稍微的不小心，可能就会带来程序的运行错误。对于页面的维护来说，非常不方便。即便是你自己写的代码，过一段时间你也可能有所遗忘，修改起来一样要备加小心。
现在有了模板，你可以把PHP代码抽取出来。我们可以这样修改second.htm文件。
<HTML>
<HEAD>
<TITLE>第二个模板文件</TITLE>
</HEAD> <BODY>
下面是一个列表
<UL>
<li>{ name1} 的身高是 {tall1}
<li>{name2} 的身高是 {tall2}
<li>{name3} 的身高是 {tall3}
<li>{name4} 的身高是 {tall4}
</UL>
</BODY>
</HTML>
建立second.php：
<?php
include (’template.inc’);
$tpl = new Template;
$tpl->set_file(’main’, ’second.htm’);
$link=mysql_connect(’localhost’,'fuyatao’,'passwd’);
$result=mysql_db_query(’fyt’,’select name,tall from my_table’);
$i=0;
while ( $a = mysql_fetch_array($result))
{
$i++;
$tpl->set_var(’name’ . $i, $a[name]);
$tpl->set_var(’tall’ . $i, $a[tall]);
}
$tpl->parse(’mains’, ‘main’);
$tpl->p(’mains’, ‘main’);
?>
在浏览器里执行 second.php 一样会得到正确的结果。这样以后不管是你还是美工修改页面的时候，再也不用胆颤心惊、担心会把程序弄坏了。
第四章 block的应用
在上一章中，我们使用模板把html和php代码分开。其中second.htm模板中关于列表部分是这样写的：
<UL>
<li>{name1} 的身高是 {tall1}
<li>{name2} 的身高是 {tall2}
<li>{name3} 的身高是 {tall3}
<li>{name4} 的身高是 {tall4}
</UL>
是不是有点烦琐？本来没用模板之前，我们用了一句
while ($a = mysql_fetch_array($result)){
echo “<li>$a[name]的身高是$a[tall]”;
} 就搞定了，用了模板，反而要写4次，如果是100人的列表，岂不是我们要写100次？天啊！够吓人的。好在phplib templete为我们提供了block，将其真译为“块”。通过定义块，也可以用一行轻松搞定。
<UL>
<!– BEGIN list –>
<li>{name} 的身高 {tall}
<!– END list –>
</UL>
需要注意的是，BEGIN list与前后的中划线–之间必须有空格，前后中划都是两个，此处可能由于显示太小，两个中划线连到一块儿了。
在 second.php中需要加载块。
<?php
include (’template.inc’);
$tpl = new Template;
$tpl->set_file(’main’, ’second.htm’);
$tpl->set_block(’main’, ‘list’, ‘nlist’); //加载模板main中的块list,并给其一个名字nlist
$link=mysql_connect(’localhost’,'fuyatao’,'passwd’);
$result=mysql_db_query(’fyt’,’select name,tall from my_table’);
while ( $a = mysql_fetch_array($result))
{
$tpl->set_var(’name’ , $a[name]);
$tpl->set_var(’tall’ , $a[tall]);
$tpl->parse(’nlist’, ‘list’, true);
}
$tpl->parse(’mains’, ‘main’);
$tpl->p(’mains’);
?>
第五章 模板嵌套
在写PHP页面的时候，我们会发现像页面头部分和尾部分，有好多页都要用，每页写一遍就太麻烦了，这些”公用代码”我们可以把它单独写在一个文件里，如果这个公用部分要有所改动,无需再去改每一个页面，能减少非常多的工作量。用Template模板可以很方便的把一个页面随意插入另一个模板的任意地方。
新建3个文件third.htm、header.htm、footer.htm，内容分为如下
third.htm
<!– 这是页面头部 –>
{header}
<BODY>
下面是一个列表
<UL>
<!– BEGIN list –>
<li>{name} 的身高是 {tall}
<!– END list –>
</UL>
<!– 这是页脚部分 –>
{footer}
</BODY>
</HTML>
header.htm
<HTML>
<HEAD>
<TITLE> {title} </TITLE>
</HEAD>
footer.htm
下面我们开始我们的PHP程序:
<?php
include (’template.inc’);
$tpl = new Template;
$tpl->set_file(’main’, ‘third.htm’);
$tpl->set_file(’my_header’, ‘header.htm’);
$tpl->set_file(’my_footer’, ‘footer.htm’);
$tpl->set_var(’title’, ‘这个是网页标题’);
$tpl->set_block(’main’, ‘list’, ‘nlist’);
$link=mysql_connect(’localhost’,'fuyatao’,'passwd’);
$result=mysql_db_query(’fyt’,’select name,tall from my_table’);
while ( $a = mysql_fetch_array($result))
{
$tpl->set_var(’name’ , $a[name]);
$tpl->set_var(’tall’ , $a[tall]);
$tpl->parse(’nlist’, ‘list’, true);
}
$tpl->parse(’header’, ‘my_header’);
$tpl->parse(footer, my_footer);
$tpl->parse(’mains’, ‘main’);
$tpl->p(’mains’);
?>
以下附上PHPLIB模板类：
复制内容到剪贴板
代码:
<?php
/*
* Session Management for PHP3
*
* (C) Copyright 1999-2000 NetUSE GmbH
* Kristian Koehntopp
*
* $Id: template.inc,v 1.12 2002/07/11 22:29:51 richardarcher Exp $
*
*/
/*
* Change log since version 7.2c
*
* Bug fixes to version 7.2c compiled by Richard Archer <rha@juggernaut.com.au>:
* (credits given to first person to post a diff to phplib mailing list)
*
* Normalised all comments and whitespace (rha)
* replaced "$handle" with "$varname" and "$h" with "$v" throughout (from phplib-devel)
* added braces around all one-line if statements in: get_undefined, loadfile and halt (rha)
* set_var was missing two sets of braces (rha)
* added a couple of "return true" statements (rha)
* set_unknowns had "keep" as default instead of "remove" (from phplib-devel)
* set_file failed to check for empty strings if passed an array of filenames (phplib-devel)
* remove @ from call to preg_replace in subst -- report errors if there are any (NickM)
* set_block unnecessarily required a newline in the template file (Marc Tardif)
* pparse now calls this->finish to replace undefined vars (Layne Weathers)
* get_var now checks for unset varnames (NickM & rha)
* get_var when passed an array used the array key instead of the value (rha)
* get_vars now uses a call to get_var rather than this->varvals to prevent undefined var warning (rha)
* in finish, the replacement string referenced an unset variable (rha)
* loadfile would try to load a file if the varval had been set to "" (rha)
* in get_undefined, only match non-whitespace in variable tags as in finish (Layne Weathers & rha)
* more elegant fix to the problem of subst stripping '$n', '\n' and '\\' strings (rha)
*
*
* Changes in functionality which go beyond bug fixes:
*
* changed debug handling so set, get and internals can be tracked separately (rha)
* added debug statements throughout to track most function calls (rha)
* debug output contained raw HTML -- is now escaped with htmlentities (rha)
* Alter regex in set_block to remove more whitespace around BEGIN/END tags to improve HTML layout (rha)
* Add "append" option to set_var, works just like append in parse (dale at linuxwebpro.com, rha)
* Altered parse so that append is honored if passed an array (Brian)
* Converted comments and documentation to phpdoc style (rha)
* Added clear_var to set the value of variables to "" (rha)
* Added unset_var to usset variables (rha)
*
*/
/**
* The template class allows you to keep your HTML code in some external files
* which are completely free of PHP code, but contain replacement fields.
* The class provides you with functions which can fill in the replacement fields
* with arbitrary strings. These strings can become very large, e.g. entire tables.
*
* Note: If you think that this is like FastTemplates, read carefully. It isn't.
*
*/
class Template
{
/**
* Serialization helper, the name of this class.
*
* @var string
* @access public
*/
var $classname = "Template";
/**
* Determines how much debugging output Template will produce.
* This is a bitwise mask of available debug levels:
* 0 = no debugging
* 1 = debug variable assignments
* 2 = debug calls to get variable
* 4 = debug internals (outputs all function calls with parameters).
*
* Note: setting $this->debug = true will enable debugging of variable
* assignments only which is the same behaviour as versions up to release 7.2d.
*
* @var int
* @access public
*/
var $debug = false;
/**
* The base directory from which template files are loaded.
*
* @var string
* @access private
* @see set_root
*/
var $root = ".";
/**
* A hash of strings forming a translation table which translates variable names
* into names of files containing the variable content.
* $file[varname] = "filename";
*
* @var array
* @access private
* @see set_file
*/
var $file = array();
/**
* A hash of strings forming a translation table which translates variable names
* into regular expressions for themselves.
* $varkeys[varname] = "/varname/"
*
* @var array
* @access private
* @see set_var
*/
var $varkeys = array();
/**
* A hash of strings forming a translation table which translates variable names
* into values for their respective varkeys.
* $varvals[varname] = "value"
*
* @var array
* @access private
* @see set_var
*/
var $varvals = array();
/**
* Determines how to output variable tags with no assigned value in templates.
*
* @var string
* @access private
* @see set_unknowns
*/
var $unknowns = "remove";
/**
* Determines how Template handles error conditions.
* "yes" = the error is reported, then execution is halted
* "report" = the error is reported, then execution continues by returning "false"
* "no" = errors are silently ignored, and execution resumes reporting "false"
*
* @var string
* @access public
* @see halt
*/
var $halt_on_error = "yes";
/**
* The last error message is retained in this variable.
*
* @var string
* @access public
* @see halt
*/
var $last_error = "";
/******************************************************************************
* Class constructor. May be called with two optional parameters.
* The first parameter sets the template directory the second parameter
* sets the policy regarding handling of unknown variables.
*
* usage: Template([string $root = "."], [string $unknowns = "remove"])
*
* @param $root path to template directory
* @param $string what to do with undefined variables
* @see set_root
* @see set_unknowns
* @access public
* @return void
*/
function Template($root = ".", $unknowns = "remove") {
if ($this->debug & 4) {
echo "<p><b>Template:</b> root = $root, unknowns = $unknowns</p>\n";
}
$this->set_root($root);
$this->set_unknowns($unknowns);
}
/******************************************************************************
* Checks that $root is a valid directory and if so sets this directory as the
* base directory from which templates are loaded by storing the value in
* $this->root. Relative filenames are prepended with the path in $this->root.
*
* Returns true on success, false on error.
*
* usage: set_root(string $root)
*
* @param $root string containing new template directory
* @see root
* @access public
* @return boolean
*/
function set_root($root) {
if ($this->debug & 4) {
echo "<p><b>set_root:</b> root = $root</p>\n";
}
if (!is_dir($root)) {
$this->halt("set_root: $root is not a directory.");
return false;
}
$this->root = $root;
return true;
}
/******************************************************************************
* Sets the policy for dealing with unresolved variable names.
*
* unknowns defines what to do with undefined template variables
* "remove" = remove undefined variables
* "comment" = replace undefined variables with comments
* "keep" = keep undefined variables
*
* Note: "comment" can cause unexpected results when the variable tag is embedded
* inside an HTML tag, for example a tag which is expected to be replaced with a URL.
*
* usage: set_unknowns(string $unknowns)
*
* @param $unknowns new value for unknowns
* @see unknowns
* @access public
* @return void
*/
function set_unknowns($unknowns = "remove") {
if ($this->debug & 4) {
echo "<p><b>unknowns:</b> unknowns = $unknowns</p>\n";
}
$this->unknowns = $unknowns;
}
/******************************************************************************
* Defines a filename for the initial value of a variable.
*
* It may be passed either a varname and a file name as two strings or
* a hash of strings with the key being the varname and the value
* being the file name.
*
* The new mappings are stored in the array $this->file.
* The files are not loaded yet, but only when needed.
*
* Returns true on success, false on error.
*
* usage: set_file(array $filelist = (string $varname => string $filename))
* or
* usage: set_file(string $varname, string $filename)
*
* @param $varname either a string containing a varname or a hash of varname/file name pairs.
* @param $filename if varname is a string this is the filename otherwise filename is not required
* @access public
* @return boolean
*/
function set_file($varname, $filename = "") {
if (!is_array($varname)) {
if ($this->debug & 4) {
echo "<p><b>set_file:</b> (with scalar) varname = $varname, filename = $filename</p>\n";
}
if ($filename == "") {
$this->halt("set_file: For varname $varname filename is empty.");
return false;
}
$this->file[$varname] = $this->filename($filename);
} else {
reset($varname);
while(list($v, $f) = each($varname)) {
if ($this->debug & 4) {
echo "<p><b>set_file:</b> (with array) varname = $v, filename = $f</p>\n";
}
if ($f == "") {
$this->halt("set_file: For varname $v filename is empty.");
return false;
}
$this->file[$v] = $this->filename($f);
}
}
return true;
}
/******************************************************************************
* A variable $parent may contain a variable block defined by:
* <!-- BEGIN $varname --> content <!-- END $varname -->. This function removes
* that block from $parent and replaces it with a variable reference named $name.
* The block is inserted into the varkeys and varvals hashes. If $name is
* omitted, it is assumed to be the same as $varname.
*
* Blocks may be nested but care must be taken to extract the blocks in order
* from the innermost block to the outermost block.
*
* Returns true on success, false on error.
*
* usage: set_block(string $parent, string $varname, [string $name = ""])
*
* @param $parent a string containing the name of the parent variable
* @param $varname a string containing the name of the block to be extracted
* @param $name the name of the variable in which to store the block
* @access public
* @return boolean
*/
function set_block($parent, $varname, $name = "") {
if ($this->debug & 4) {
echo "<p><b>set_block:</b> parent = $parent, varname = $varname, name = $name</p>\n";
}
if (!$this->loadfile($parent)) {
$this->halt("set_block: unable to load $parent.");
return false;
}
if ($name == "") {
$name = $varname;
}
$str = $this->get_var($parent);
$reg = "/[ \t]*<!--\s+BEGIN $varname\s+-->\s*?\n?(\s*.*?\n?)\s*<!--\s+END $varname\s+-->\s*?\n?/sm";
preg_match_all($reg, $str, $m);
$str = preg_replace($reg, "{" . "$name}", $str);
$this->set_var($varname, $m[1][0]);
$this->set_var($parent, $str);
return true;
}
/******************************************************************************
* This functions sets the value of a variable.
*
* It may be called with either a varname and a value as two strings or an
* an associative array with the key being the varname and the value being
* the new variable value.
*
* The function inserts the new value of the variable into the $varkeys and
* $varvals hashes. It is not necessary for a variable to exist in these hashes
* before calling this function.
*
* An optional third parameter allows the value for each varname to be appended
* to the existing variable instead of replacing it. The default is to replace.
* This feature was introduced after the 7.2d release.
*
*
* usage: set_var(string $varname, [string $value = ""], [boolean $append = false])
* or
* usage: set_var(array $varname = (string $varname => string $value), [mixed $dummy_var], [boolean $append = false])
*
* @param $varname either a string containing a varname or a hash of varname/value pairs.
* @param $value if $varname is a string this contains the new value for the variable otherwise this parameter is ignored
* @param $append if true, the value is appended to the variable's existing value
* @access public
* @return void
*/
function set_var($varname, $value = "", $append = false) {
if (!is_array($varname))//如果不是阵列
{
if (!empty($varname)) //如果是空的
{
if ($this->debug & 1) {
printf("<b>set_var:</b> (with scalar) <b>%s</b> = '%s'<br>\n", $varname, htmlentities($value));
}
$this->varkeys[$varname] = "/".$this->varname($varname)."/";
if ($append && isset($this->varvals[$varname])) {
$this->varvals[$varname] .= $value;
} else {
$this->varvals[$varname] = $value;
}
}
} else {
reset($varname);
while(list($k, $v) = each($varname)) {
if (!empty($k)) {
if ($this->debug & 1) {
printf("<b>set_var:</b> (with array) <b>%s</b> = '%s'<br>\n", $k, htmlentities($v));
}
$this->varkeys[$k] = "/".$this->varname($k)."/";
if ($append && isset($this->varvals[$k])) {
$this->varvals[$k] .= $v;
} else {
$this->varvals[$k] = $v;
}
}
}
}
}
/******************************************************************************
* This functions clears the value of a variable.
*
* It may be called with either a varname as a string or an array with the
* values being the varnames to be cleared.
*
* The function sets the value of the variable in the $varkeys and $varvals
* hashes to "". It is not necessary for a variable to exist in these hashes
* before calling this function.
*
*
* usage: clear_var(string $varname)
* or
* usage: clear_var(array $varname = (string $varname))
*
* @param $varname either a string containing a varname or an array of varnames.
* @access public
* @return void
*/
function clear_var($varname) {
if (!is_array($varname)) {
if (!empty($varname)) {
if ($this->debug & 1) {
printf("<b>clear_var:</b> (with scalar) <b>%s</b><br>\n", $varname);
}
$this->set_var($varname, "");
}
} else {
reset($varname);
while(list($k, $v) = each($varname)) {
if (!empty($v)) {
if ($this->debug & 1) {
printf("<b>clear_var:</b> (with array) <b>%s</b><br>\n", $v);
}
$this->set_var($v, "");
}
}
}
}
/******************************************************************************
* This functions unsets a variable completely.
*
* It may be called with either a varname as a string or an array with the
* values being the varnames to be cleared.
*
* The function removes the variable from the $varkeys and $varvals hashes.
* It is not necessary for a variable to exist in these hashes before calling
* this function.
*
*
* usage: unset_var(string $varname)
* or
* usage: unset_var(array $varname = (string $varname))
*
* @param $varname either a string containing a varname or an array of varnames.
* @access public
* @return void
*/
function unset_var($varname) {
if (!is_array($varname)) {
if (!empty($varname)) {
if ($this->debug & 1) {
printf("<b>unset_var:</b> (with scalar) <b>%s</b><br>\n", $varname);
}
unset($this->varkeys[$varname]);
unset($this->varvals[$varname]);
}
} else {
reset($varname);
while(list($k, $v) = each($varname)) {
if (!empty($v)) {
if ($this->debug & 1) {
printf("<b>unset_var:</b> (with array) <b>%s</b><br>\n", $v);
}
unset($this->varkeys[$v]);
unset($this->varvals[$v]);
}
}
}
}
/******************************************************************************
* This function fills in all the variables contained within the variable named
* $varname. The resulting value is returned as the function result and the
* original value of the variable varname is not changed. The resulting string
* is not "finished", that is, the unresolved variable name policy has not been
* applied yet.
*
* Returns: the value of the variable $varname with all variables substituted.
*
* usage: subst(string $varname)
*
* @param $varname the name of the variable within which variables are to be substituted
* @access public
* @return string
*/
function subst($varname) {
$varvals_quoted = array();
if ($this->debug & 4) {
echo "<p><b>subst:</b> varname = $varname</p>\n";
}
if (!$this->loadfile($varname)) {
$this->halt("subst: unable to load $varname.");
return false;
}
// quote the replacement strings to prevent bogus stripping of special chars
reset($this->varvals);
while(list($k, $v) = each($this->varvals)) {
$varvals_quoted[$k] = preg_replace(array('/\\\\/', '/\$/'), array('\\\\\\\\', '\\\\$'), $v);
}
$str = $this->get_var($varname);
$str = preg_replace($this->varkeys, $varvals_quoted, $str);
return $str;
}
/******************************************************************************
* This is shorthand for print $this->subst($varname). See subst for further
* details.
*
* Returns: always returns false.
*
* usage: psubst(string $varname)
*
* @param $varname the name of the variable within which variables are to be substituted
* @access public
* @return false
* @see subst
*/
function psubst($varname) {
if ($this->debug & 4) {
echo "<p><b>psubst:</b> varname = $varname</p>\n";
}
print $this->subst($varname);
return false;
}
/******************************************************************************
* The function substitutes the values of all defined variables in the variable
* named $varname and stores or appends the result in the variable named $target.
*
* It may be called with either a target and a varname as two strings or a
* target as a string and an array of variable names in varname.
*
* The function inserts the new value of the variable into the $varkeys and
* $varvals hashes. It is not necessary for a variable to exist in these hashes
* before calling this function.
*
* An optional third parameter allows the value for each varname to be appended
* to the existing target variable instead of replacing it. The default is to
* replace.
*
* If $target and $varname are both strings, the substituted value of the
* variable $varname is inserted into or appended to $target.
*
* If $handle is an array of variable names the variables named by $handle are
* sequentially substituted and the result of each substitution step is
* inserted into or appended to in $target. The resulting substitution is
* available in the variable named by $target, as is each intermediate step
* for the next $varname in sequence. Note that while it is possible, it
* is only rarely desirable to call this function with an array of varnames
* and with $append = true. This append feature was introduced after the 7.2d
* release.
*
* Returns: the last value assigned to $target.
*
* usage: parse(string $target, string $varname, [boolean $append])
* or
* usage: parse(string $target, array $varname = (string $varname), [boolean $append])
*
* @param $target a string containing the name of the variable into which substituted $varnames are to be stored
* @param $varname if a string, the name the name of the variable to substitute or if an array a list of variables to be substituted
* @param $append if true, the substituted variables are appended to $target otherwise the existing value of $target is replaced
* @access public
* @return string
* @see subst
*/
function parse($target, $varname, $append = false) {
if (!is_array($varname)) {
if ($this->debug & 4) {
echo "<p><b>parse:</b> (with scalar) target = $target, varname = $varname, append = $append</p>\n";
}
$str = $this->subst($varname);
if ($append) {
$this->set_var($target, $this->get_var($target) . $str);
} else {
$this->set_var($target, $str);
}
} else {
reset($varname);
while(list($i, $v) = each($varname)) {
if ($this->debug & 4) {
echo "<p><b>parse:</b> (with array) target = $target, i = $i, varname = $v, append = $append</p>\n";
}
$str = $this->subst($v);
if ($append) {
$this->set_var($target, $this->get_var($target) . $str);
} else {
$this->set_var($target, $str);
}
}
}
if ($this->debug & 4) {
echo "<p><b>parse:</b> completed</p>\n";
}
return $str;
}
/******************************************************************************
* This is shorthand for print $this->parse(...) and is functionally identical.
* See parse for further details.
*
* Returns: always returns false.
*
* usage: pparse(string $target, string $varname, [boolean $append])
* or
* usage: pparse(string $target, array $varname = (string $varname), [boolean $append])
*
* @param $target a string containing the name of the variable into which substituted $varnames are to be stored
* @param $varname if a string, the name the name of the variable to substitute or if an array a list of variables to be substituted
* @param $append if true, the substituted variables are appended to $target otherwise the existing value of $target is replaced
* @access public
* @return false
* @see parse
*/
function pparse($target, $varname, $append = false) {
if ($this->debug & 4) {
echo "<p><b>pparse:</b> passing parameters to parse...</p>\n";
}
print $this->finish($this->parse($target, $varname, $append));
return false;
}
/******************************************************************************
* This function returns an associative array of all defined variables with the
* name as the key and the value of the variable as the value.
*
* This is mostly useful for debugging. Also note that $this->debug can be used
* to echo all variable assignments as they occur and to trace execution.
*
* Returns: a hash of all defined variable values keyed by their names.
*
* usage: get_vars()
*
* @access public
* @return array
* @see $debug
*/
function get_vars() {
if ($this->debug & 4) {
echo "<p><b>get_vars:</b> constructing array of vars...</p>\n";
}
reset($this->varkeys);
while(list($k, $v) = each($this->varkeys)) {
$result[$k] = $this->get_var($k);
}
return $result;
}
/******************************************************************************
* This function returns the value of the variable named by $varname.
* If $varname references a file and that file has not been loaded yet, the
* variable will be reported as empty.
*
* When called with an array of variable names this function will return a a
* hash of variable values keyed by their names.
*
* Returns: a string or an array containing the value of $varname.
*
* usage: get_var(string $varname)
* or
* usage: get_var(array $varname)
*
* @param $varname if a string, the name the name of the variable to get the value of, or if an array a list of variables to return the value of
* @access public
* @return string or array
*/
function get_var($varname) {
if (!is_array($varname)) {
if (isset($this->varvals[$varname])) {
$str = $this->varvals[$varname];
} else {
$str = "";
}
if ($this->debug & 2) {
printf ("<b>get_var</b> (with scalar) <b>%s</b> = '%s'<br>\n", $varname, htmlentities($str));
}
return $str;
} else {
reset($varname);
while(list($k, $v) = each($varname)) {
if (isset($this->varvals[$v])) {
$str = $this->varvals[$v];
} else {
$str = "";
}
if ($this->debug & 2) {
printf ("<b>get_var:</b> (with array) <b>%s</b> = '%s'<br>\n", $v, htmlentities($str));
}
$result[$v] = $str;
}
return $result;
}
}
/******************************************************************************
* This function returns a hash of unresolved variable names in $varname, keyed
* by their names (that is, the hash has the form $a[$name] = $name).
*
* Returns: a hash of varname/varname pairs or false on error.
*
* usage: get_undefined(string $varname)
*
* @param $varname a string containing the name the name of the variable to scan for unresolved variables
* @access public
* @return array
*/
function get_undefined($varname) {
if ($this->debug & 4) {
echo "<p><b>get_undefined:</b> varname = $varname</p>\n";
}
if (!$this->loadfile($varname)) {
$this->halt("get_undefined: unable to load $varname.");
return false;
}
preg_match_all("/{([^ \t\r\n}]+)}/", $this->get_var($varname), $m);
$m = $m[1];
if (!is_array($m)) {
return false;
}
reset($m);
while(list($k, $v) = each($m)) {
if (!isset($this->varkeys[$v])) {
if ($this->debug & 4) {
echo "<p><b>get_undefined:</b> undefined: $v</p>\n";
}
$result[$v] = $v;
}
}
if (count($result)) {
return $result;
} else {
return false;
}
}
/******************************************************************************
* This function returns the finished version of $str. That is, the policy
* regarding unresolved variable names will be applied to $str.
*
* Returns: a finished string derived from $str and $this->unknowns.
*
* usage: finish(string $str)
*
* @param $str a string to which to apply the unresolved variable policy
* @access public
* @return string
* @see set_unknowns
*/
function finish($str) {
switch ($this->unknowns) {
case "keep":
break;
case "remove":
$str = preg_replace('/{[^ \t\r\n}]+}/', "", $str);
break;
case "comment":
$str = preg_replace('/{([^ \t\r\n}]+)}/', "<!-- Template variable \\1 undefined -->", $str);
break;
}
return $str;
}
/******************************************************************************
* This function prints the finished version of the value of the variable named
* by $varname. That is, the policy regarding unresolved variable names will be
* applied to the variable $varname then it will be printed.
*
* usage: p(string $varname)
*
* @param $varname a string containing the name of the variable to finish and print
* @access public
* @return void
* @see set_unknowns
* @see finish
*/
function p($varname) {
print $this->finish($this->get_var($varname));
}
/******************************************************************************
* This function returns the finished version of the value of the variable named
* by $varname. That is, the policy regarding unresolved variable names will be
* applied to the variable $varname and the result returned.
*
* Returns: a finished string derived from the variable $varname.
*
* usage: get(string $varname)
*
* @param $varname a string containing the name of the variable to finish
* @access public
* @return void
* @see set_unknowns
* @see finish
*/
function get($varname) {
return $this->finish($this->get_var($varname));
}
/******************************************************************************
* When called with a relative pathname, this function will return the pathname
* with $this->root prepended. Absolute pathnames are returned unchanged.
*
* Returns: a string containing an absolute pathname.
*
* usage: filename(string $filename)
*
* @param $filename a string containing a filename
* @access private
* @return string
* @see set_root
*/
function filename($filename) {
if ($this->debug & 4) {
echo "<p><b>filename:</b> filename = $filename</p>\n";
}
if (substr($filename, 0, 1) != "/") {
$filename = $this->root."/".$filename;
}
if (!file_exists($filename)) {
$this->halt("filename: file $filename does not exist.");
}
return $filename;
}
/******************************************************************************
* This function will construct a regexp for a given variable name with any
* special chars quoted.
*
* Returns: a string containing an escaped variable name.
*
* usage: varname(string $varname)
*
* @param $varname a string containing a variable name
* @access private
* @return string
*/
function varname($varname) {
return preg_quote("{".$varname."}");
}
/******************************************************************************
* If a variable's value is undefined and the variable has a filename stored in
* $this->file[$varname] then the backing file will be loaded and the file's
* contents will be assigned as the variable's value.
*
* Note that the behaviour of this function changed slightly after the 7.2d
* release. Where previously a variable was reloaded from file if the value
* was empty, now this is not done. This allows a variable to be loaded then
* set to "", and also prevents attempts to load empty variables. Files are
* now only loaded if $this->varvals[$varname] is unset.
*
* Returns: true on success, false on error.
*
* usage: loadfile(string $varname)
*
* @param $varname a string containing the name of a variable to load
* @access private
* @return boolean
* @see set_file
*/
function loadfile($varname) {
if ($this->debug & 4) {
echo "<p><b>loadfile:</b> varname = $varname</p>\n";
}
if (!isset($this->file[$varname])) {
// $varname does not reference a file so return
if ($this->debug & 4) {
echo "<p><b>loadfile:</b> varname $varname does not reference a file</p>\n";
}
return true;
}
if (isset($this->varvals[$varname])) {
// will only be unset if varname was created with set_file and has never been loaded
// $varname has already been loaded so return
if ($this->debug & 4) {
echo "<p><b>loadfile:</b> varname $varname is already loaded</p>\n";
}
return true;
}
$filename = $this->file[$varname];
/* use @file here to avoid leaking filesystem information if there is an error */
$str = implode("", @file($filename));
if (empty($str)) {
$this->halt("loadfile: While loading $varname, $filename does not exist or is empty.");
return false;
}
if ($this->debug & 4) {
printf("<b>loadfile:</b> loaded $filename into $varname<br>\n");
}
$this->set_var($varname, $str);
return true;
}
/******************************************************************************
* This function is called whenever an error occurs and will handle the error
* according to the policy defined in $this->halt_on_error. Additionally the
* error message will be saved in $this->last_error.
*
* Returns: always returns false.
*
* usage: halt(string $msg)
*
* @param $msg a string containing an error message
* @access private
* @return void
* @see $halt_on_error
*/
function halt($msg) {
$this->last_error = $msg;
if ($this->halt_on_error != "no") {
$this->haltmsg($msg);
}
if ($this->halt_on_error == "yes") {
die("<b>Halted.</b>");
}
return false;
}
/******************************************************************************
* This function prints an error message.
* It can be overridden by your subclass of Template. It will be called with an
* error message to display.
*
* usage: haltmsg(string $msg)
*
* @param $msg a string containing the error message to display
* @access public
* @return void
* @see halt
*/
function haltmsg($msg) {
printf("<b>Template Error:</b> %s<br>\n", $msg);
}
}
?>
