Files
smarty/doc.sgm
2001-01-09 17:11:32 +00:00

1584 lines
51 KiB
Plaintext

<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
<book>
<bookinfo>
<title>Smarty - the compiling PHP template engine</title>
<author><firstname>Monte</firstname><surname>Ohrt</surname></author>
<author><firstname>Andrei</firstname><surname>Zmievski</surname></author>
<copyright><year>2001</year><holder>ispi, Inc.</holder></copyright>
</bookinfo>
<chapter>
<title>Overview</title>
<para>
It is undoubtedly one of the most asked questions on the PHP mailing
lists: how do I make my PHP scripts independent of the layout? While
PHP is billed as "HTML embedded scripting language", after writing a
couple of projects that mixed PHP and HTML freely one comes up with
the idea that separation of form and content is a Good Thing [TM]. In
addition, in many companies the roles of layout designer and programmer
are separate. Consequently, the search for a templating solution ensues.
</para>
<para>
In our company for example, the development of an application goes on
as follows. After the requirements docs are done, the interface designer
makes mockups of the interface and gives them to the programmer. The
programmer implements business logic in PHP and uses interface mockups
to create skeleton templates. The project is then handed off to the HTML
designer/web page layout person who brings the templates up to their full
glory. The project may go back and forth between programming/HTML a couple
of times. Thus, it's important to have good template support because
programmers don't want anything to do with HTML and don't want HTML
designers mucking around with PHP code, and designers need support for
config files, dynamic blocks and other stuff, but they don't want to
have to deal with intricacies of the PHP programming language.
</para>
<para>
Looking at many templating solutions available for PHP today,
most of them provide a rudimentary way of substituting variables into
templates and do a limited form of dynamic block functionality (a section
of a template that is looped over and over with a set of indexed variables).
But our needs were a bit more than that. We didn't want programmers to be
dealing with HTML layout at ALL, but this was almost inevitable. For
instance, if a designer wanted background colors to alternate on dynamic
blocks, this had to be worked out with the programmer in advance. We also
needed designers to be able to use their own configuration files, and pull
variables from them into the templates. The list goes on.
</para>
<para>
We started out writing out a spec for a template engine about a year ago.
After finishing the spec, we began to work on a template engine written in
C that would hopefully be accepted for inclusion with PHP. Not only did we
run into many complicated technical barriers, but there was also much heated
debate about exactly what a template engine should and should not do. From
this experience, we decided that the template engine should be written in PHP
as a class, for anyone to use as they see fit. So we wrote an engine that did
just that. "SmartTemplate" came to existance (note: this class was never
submitted to the public). It was a class that did almost everything we wanted:
regular variable substitution, supported including other templates, integration
with config files, embedding PHP code, limited 'if' statement functionality and
much more robust dynamic blocks which could be multiply nested. It did all this
with regular expressions and the code turned out to be rather, shall we say,
impenetrable. It was also noticably slow in large applications from all the
parsing and regular expression work it had to do on each invocation.
</para>
<para>
Then came the vision of what ultimately became Smarty. We know how fast PHP
code is without the overhead of template parsing. We also know how meticulous
and overbearing the language may look to the average designer, and this could
be masked with a much simpler templating syntax. So what if we combined the two
strengths? Thus, Smarty was born...
</para>
<sect1><title>What is Smarty?</title>
<para>
Smarty is a template engine for PHP. One of the unique aspects about
Smarty that sets it apart from other templating solutions is that it
compiles the templates into native php scripts upon the first
invocation. After that, it merely executes the compiled PHP scripts.
Therefore, there is no costly template file parsing for each request.
</para>
<para>
Some of Smarty's features:
</para>
<itemizedlist>
<listitem><para>It is extremely fast.</para></listitem>
<listitem><para>It is relatively simple since the PHP parser does the
dirty work.</para></listitem>
<listitem><para>No template parsing overhead, only compiles once.</para></listitem>
<listitem><para>It is smart about recompiling only the template
files that have changed.</para></listitem>
<listitem><para>You can make custom functions and custom variable modifiers, so
the template language is extremely extensible.</para></listitem>
<listitem><para>Configurable template delimiter tag syntax, so you can use
{}, {{}}, &lt;!--{}--&gt;, or whatever you like.</para></listitem>
<listitem><para>Template if/else/endif constructs are passed to the PHP parser,
so the if syntax can be as simple or as complex as you like.</para></listitem>
<listitem><para>Unlimited nesting of sections,ifs, etc. allowed.</para></listitem>
<listitem><para>It is possible to imbed PHP code right in your template files,
although doubtfully needed since the engine is so customizable.</para></listitem>
</itemizedlist>
</sect1>
<sect1>
<title>How Smarty works</title>
<sect2><title>compiling</title>
<para>
Smarty compiles the templates into native PHP code on-the-fly. The actual
PHP scripts that are generated are created implicitly, so theoretically you
should never have to worry about touching these files, or even know of their
existance. The exception to this is debugging Smarty template syntax errors,
discussed later in this document.
</para>
</sect2>
<sect2><title>caching</title>
<para>
Our initial intention was to build caching into Smarty. However,
since the template engine is actually executing PHP scripts instead of
parsing template files, the need for a cache was dramatically reduced.
We may implement this in a future version of Smarty as the need arises.
</para>
</sect2>
</sect1>
</chapter>
<chapter>
<title>Installation</title>
<sect1>
<title>Requirements</title>
<para>
Smarty requires PHP 4.0.4pl1 or later. 4.0.4 contains a bug that
crashes PHP when certain Smarty features are used (such as the @count modifier).
4.0.3 and earlier contain a bug in preg_grep() that won't allow the parser to
function properly. We may make some adjusments to work around these
issues in future versions of Smarty. For now, get the very latest version of PHP.
As of this writing, 4.0.4pl1 is not yet available, so a CVS snapshot is necessary.
</para>
</sect1>
<sect1>
<title>Installing Smarty</title>
<para>
Installing Smarty is fairly straight forward, there is just one thing you must
be aware of. Remember that Smarty creates compiled versions of the template code.
This usually means allowing user "nobody" (or whomever the web server runs
as) to have permission to write the files. Each installation of a Smarty
application minimally needs a template directory, a config file directory and a compiled
template directory. By default these are named "templates","configs" and "templates_c"
respectively.
</para>
<para>
Copy the Smarty.class.php and Smarty.addons.php scripts to a
directory that is in your PHP include_path. NOTE: php will try to create a
directory along side the index.php script called "templates_c". Be sure
that directory permissions allow this to happen. You will see appropriate
error messages if this fails. You can also create the directory yourself
before hand, and change the file ownership accordingly. See below.
</para>
<example>
<title>Example of installing Smarty</title>
<programlisting>
# be sure you are in the web server document tree
# this assumes your web server runs as user "nobody"
# and you are in a unix environment
gtar -zxvf Smarty-1.0.tar.gz
touch templates_c
chown nobody:nobody templates_c
</programlisting>
</example>
<para>
Next, try running the index.php script from your web browser.
</para>
</sect1>
</chapter>
<chapter>
<title>Setting up Smarty</title>
<para>
There are several variables that are at the top of the Smarty.class.php file. You
can usually get away with leaving these at their default settings. This is a list
of them and what each one does.
</para>
<sect1>
<title>Configuration variables</title>
<para></para>
<sect2>
<title>$compile_check</title>
<para>
Upon each invocation of the PHP application, Smarty traverses all the template
files and searches for any that have changed (later datestamp) since the last time the
application was invoked. For each one that has changed, it recompiles that
template. By default this is set to true. The compile check has very
minimal impact on the application performance. However, once an application
is put into production and it is initially compiled, the compile_check step
is no longer needed. You may set this to "false" *after* the initial compile. Then
Smarty will no longer check for changed template files. Note that if you change
this to "false" and a template file is changed, you will *not* see the change since
the template will not get recompiled. Set it to "true", invoke the application,
then set it back to "false".
</para>
</sect2>
<sect2>
<title>$template_dir</title>
<para>
This is the directory name that template files are kept in.
</para>
</sect2>
<sect2>
<title>$compile_dir_ext</title>
<para>
This is the extension used for the name of the directory that compiled templates
are kept in. By default this is "_c". Therefore if your template directory is
named "templates", then the compile directory will be named "templates_c".
</para>
</sect2>
<sect2>
<title>$tpl_file_ext</title>
<para>
This is the extention used for template files. By default this is ".tpl".
All other files in the template directory are ignored.
</para>
</sect2>
<sect2>
<title>$max_recursion_depth</title>
<para>
This is the maximum depth you can include other templates within templates.
This is to help catch infinite loops when template files accidentally include
each other.
</para>
</sect2>
<sect2>
<title>$allow_php</title>
<para>
Whether or not to allow PHP code to be imbedded into the
templates. If set to false, PHP code is escaped and not interpreted. Imbedding
PHP code into templates is highly discouraged. Use custom functions or modifiers
instead. Default is "false".
</para>
</sect2>
<sect2>
<title>$left_delimiter</title>
<para>
This is the left delimiter syntax in the templates. Default is "{".
</para>
</sect2>
<sect2>
<title>$right_delimiter</title>
<para>
This is the right delimiter syntax in the templates. Default is "}".
</para>
</sect2>
<sect2>
<title>$config_dir</title>
<para>
This is the directory used to store config files used in the templates.
Default is "configs".
</para>
</sect2>
<sect2>
<title>$custom_funcs</title>
<para>
This is a mapping of the names of custom functions in the template to
the names of functions in PHP. These are usually kept in Smarty.addons.php.
</para>
</sect2>
<sect2>
<title>$custom_mods</title>
<para>
This is a mapping of the names of variable modifiers in the template to
the names of functions in PHP. These are usually kept in Smarty.addons.php.
</para>
</sect2>
<sect2>
<title>$global_assign</title>
<para>
This is a list of variables that are always implicitly assigned to the
template engine. This is usually handy for making global variables or server
variables available to the template without having to manually assign them to
the template every time.
</para>
</sect2>
</sect1>
</chapter>
<chapter>
<title>Smarty API</title>
<para>
These functions are used in the PHP portion of your application.
</para>
<sect1>
<title>Smarty API Functions</title>
<sect2>
<title>assign</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>assign</function></funcdef>
<paramdef>mixed <parameter>var</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>assign</function></funcdef>
<paramdef>string <parameter>varname</parameter></paramdef>
<paramdef>mixed <parameter>var</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This is used to assign values to the templates. This is usually
data gathered from database queries or other sources of data.
</para>
</sect2>
<sect2>
<title>append</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>append</function></funcdef>
<paramdef>mixed <parameter>var</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>append</function></funcdef>
<paramdef>string <parameter>varname</parameter></paramdef>
<paramdef>mixed <parameter>var</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This is used to append data to existing variables in the template.
</para>
</sect2>
<sect2>
<title>clear_assign</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>clear_assign</function></funcdef>
<paramdef>string <parameter>var</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This clears the value of an assigned variable.
</para>
</sect2>
<sect2>
<title>clear_all_assign</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>clear_all_assign</function></funcdef>
<paramdef><parameter></parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This clears the values of all assigned variables.
</para>
</sect2>
<sect2>
<title>get_template_vars</title>
<funcsynopsis>
<funcprototype>
<funcdef>array <function>get_template_vars</function></funcdef>
<paramdef><parameter></parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This gets an array of the currently assigned template vars.
</para>
</sect2>
<sect2>
<title>display</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>display</function></funcdef>
<paramdef>string <parameter>template</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This displays the template.
</para>
</sect2>
<sect2>
<title>fetch</title>
<funcsynopsis>
<funcprototype>
<funcdef>string <function>fetch</function></funcdef>
<paramdef>string <parameter>template</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<para>
This returns the template output.
</para>
</sect2>
<sect2>
<title>Using Smarty API</title>
<example>
<title>Example use of Smarty API</title>
<programlisting>
include("Smarty.class.php");
$smarty = new Smarty;
// dummy up some data
$address = "245 N 50th";
$db_data = array(
"City" => "Lincoln",
"State" => "Nebraska",
"Zip" = > "68502"
);
$smarty->assign("Name","Fred");
$smarty->assign("Address",$address);
$smarty->assign($db_data);
// display the output
$smarty->display("./templates/index.tpl");
// alternatively capture the output
$output = $smarty->fetch("./templates/index.tpl");
</programlisting>
</example>
</sect2>
</sect1>
</chapter>
<chapter>
<title>Smarty Templates</title>
<para>
The templates are the heart of Smarty. These are the files that the designers
work with. They're basically pages made up of static content interspersed with
template markup tags. These tags are placeholders for variables or blocks of logic.
</para>
<sect1>
<title>Syntax</title>
<para>
For these examples, we will assume that you are using the default
template tag delimiters, which are "{" and "}". In Smarty, all content
outside of delimiter tags is displayed as static content, or unchanged.
When Smarty encounters template tags {}, it attempts to interpret what is
between the tags, and displays the appropriate output in place of them.
</para>
<sect2>
<title>Variables</title>
<para>
There are three basic types of variables in Smarty, each with their
own unique syntax.
</para>
<sect3>
<title>Variables assigned from PHP</title>
<para>
Variables that are assigned from PHP are displayed by preceeding
them with a dollar sign ($) and enclosing the variable in delimiters
like so: {$varname}
</para>
<example>
<title>Template example of displaying assigned variables</title>
<programlisting>
Hello {$firstname}, glad to see you could make it.
&lt;p&gt;
Your last login was on {$lastLoginDate}
</programlisting>
</example>
<para>
There are also variables within looping sections that are displayed
a bit differently, with the section name prepended like so: {$secname/varname}.
Those are exaplained later in this document under Built-in Functions.
</para>
</sect3>
<sect3>
<title>Variables passed from config files</title>
<para>
Variables that are passed in from config files are displayed by enclosing
them with hash marks (#) and enclosing the variable in delimiters
like so: {#varname#}
</para>
<example>
<title>Template example of displaying config variables</title>
<programlisting>
&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
&lt;tr bgcolor="{#rowBgColor#}"&gt;
&lt;td&gt;First&lt;/td&gt;
&lt;td&gt;Last&lt;/td&gt;
&lt;td&gt;Address&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
<para>
Config file variables cannot be displayed until
after they are loaded in from a config file. This procedure is
explained later in this document under Built-in Functions.
</para>
</sect3>
<sect3>
<title>Variables internal to template</title>
<para>
Variables that are internal to the templates are displayed by enclosing
them with percent signs (%) and enclosing the variable in delimiters
like so: {%varname%} These are usually used in looping sections, so
you will most likely see the variable prepended with the section name
like so: {%secname.varname%}. These are explained in detail later
in this document under Built-in Functions.
</para>
</sect3>
</sect2>
<sect2>
<title>Functions</title>
<para>
Functions are processed and displayed by enclosing the function and its
attributes into delimiters like so: {funcname attr1="val" attr2="val"}
</para>
<example>
<title>Template example of function syntax</title>
<programlisting>
{config_load file="colors.conf"}
{include file="header.tpl"}
{if $name eq "Fred"}
You are not allowed here
{else}
Welcome, &lt;font color="{#fontColor#}"&gt;{$name}!&lt;/font&gt;
{/if}
{include file="footer.tpl"}
</programlisting>
</example>
<para>
Both built-in functions and custom functions work exactly the same
way syntactically.
</para>
</sect2>
<sect2>
<title>Attributes</title>
<para>
Attributes to functions are much like HTML attributes. Static
values don't have to be enclosed in quotes, but is recommended.
If not quoted, you may use a syntax that Smarty may confuse
with another function, such as a boolean value. Variables may
also be used, and should not be in parenthesis.
</para>
<example>
<title>Template example of function attribute syntax</title>
<programlisting>
{include file="header.tpl"}
{include file=$includeFile}
{include file=#includeFile#}
{html_options values=$vals selected=$selected output=$output}
</programlisting>
</example>
</sect2>
<sect2>
<title>Comments</title>
<para>
Template comments are surrounded by asterisks, and that is surrounded
by the delimiter tags like so: {* this is a comment *}
Smarty comments are not displayed in the final output of the template.
They are used mainly for making the templates more understandable.
</para>
<example>
<title>Template example of Comments</title>
<programlisting>
{* Smarty *}
{* include the header file here *}
{include file="header.tpl"}
{include file=$includeFile}
{include file=#includeFile#}
{* display dropdown lists *}
{html_options values=$vals selected=$selected output=$output}
</programlisting>
</example>
</sect2>
</sect1>
<sect1>
<title>Config Files</title>
<para>
Config files are handy for designers to manage global
template variables from one file. One example is template colors.
Normally if you wanted to change the color scheme of an application,
you would have to go through each and every template file
and change the colors. With a config file, the colors can
be kept in one place, and only one file needs to be updated.
</para>
<example>
<title>Example of config file syntax</title>
<programlisting>
# global variables
pageTitle = "Main Menu"
bodyBgColor = #000000
tableBgColor = #000000
rowBgColor = #00ff00
[Customer]
pageTitle = "Customer Info"
[Login]
pageTitle = "Login"
focus = "username"
Intro = """This is a value that spans more
than one line. you must enclose
it in triple quotes."""
</programlisting>
</example>
<para>
Values of config file variables can be in qoutes, but not necessary.
You can use either single or double quotes. If you have a value that
spans more than one line, enclose the entire value with triple quotes
("""). You can put comments into config files by any syntax that is
not a valid config file syntax. We recommend using a hashmark (#) at the
beginning of the line.
</para>
<para>
This config file example has two sections. Section names are enclosed
in brackets []. The four variables at the top are global
variables, or variables not within a section. These variables are
always loaded from the config file.
If a particular section is loaded, then the global variables and the
variables from that section are loaded. If a variable exists both as
a global and in a section, the section variable is used. If you name two
variables the same within a section, the last one will be used.
</para>
<para>
Config files are loaded into templates with the built-in function
called config_load. See Built-In functions for examples.
</para>
</sect1>
<sect1>
<title>Built-in Functions</title>
<para>
Smarty comes with several built-in functions. Built-in functions
are integral to the template language. You cannot create custom
functions with the same names, nor can you modify built-in functions.
</para>
<sect2>
<title>config_load</title>
<para>
This function is used for loading in variables from a
configuration file into the template.
</para>
<example>
<title>Template example of function config_load</title>
<programlisting>
{config_load file="colors.conf"}
&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
&lt;tr bgcolor="{#rowBgColor#}"&gt;
&lt;td&gt;First&lt;/td&gt;
&lt;td&gt;Last&lt;/td&gt;
&lt;td&gt;Address&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
<para>
Config files may also contain sections. You can load
variables from within a section with the added attribute
"section".
</para>
<example>
<title>Template example of function config_load with section</title>
<programlisting>
{config_load file="colors.conf" section="Customer"}
&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
&lt;tr bgcolor="{#rowBgColor#}"&gt;
&lt;td&gt;First&lt;/td&gt;
&lt;td&gt;Last&lt;/td&gt;
&lt;td&gt;Address&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
</sect2>
<sect2>
<title>include</title>
<para>
Include tags are used for including other templates into
the current template. When a template is included, it
inherits all the variables available to the current template.
The include tag must have the attribute "file", which
contains the path to the included template file relative
to the template directory.
</para>
<example>
<title>Template example of function include</title>
<programlisting>
{include file="header.tpl"}
{* body of template goes here *}
{include file="footer.tpl"}
</programlisting>
</example>
<para>
You can also pass variables to included templates as attributes.
These will be passed to the template along with the current
template variables. Attribute variables override template
variables, in the case they are named alike. You can
pass either static content or other variables to included templates.
</para>
<example>
<title>Template example of function include passing variables</title>
<programlisting>
{include file="header.tpl" title="Main Menu" company=$companyName}
{* body of template goes here *}
{include file="footer.tpl" logo="http://my.domain.com/logo.gif"}
</programlisting>
</example>
</sect2>
<sect2>
<title>insert</title>
<para>
The insert tag in Smarty serves a special purpose. You may
run into the situation where it is impossible to pass data to a template
before the template is executed because there is info in the template
needed to aquire the data, kind of a catch 22. The insert tag is a way
to callback a function in PHP during runtime of the template.
</para>
<para>
Let's say you have a page with a banner slot at the top. The template
has banner_id and page_id values, and needs to call a function to get the banner.
</para>
<example>
<title>Template example of function insert</title>
<programlisting>
{* example of fetching a banner *}
{insert name="getBanner" banner_id=#banner_id# page_id=#page_id#}
</programlisting>
</example>
<para>
In this example, we are using the name "getBanner" and passing #banner_id#
and #page_id# (which was pulled out of a configuration file). Smarty will look
for a function named insert_getBanner() in your PHP application, passing
the value of #banner_id# and #page_id# as the first argument in an indexed
array. All insert function names in
your application must be prepended with "insert_" to be sure there are
no function name-space conflicts. Your insert_getBanner() function should
do something with the passed values and return the results. These results
are then displayed in the template in place of the insert tag. All values
passed to an insert function are passed as the first argument in an indexed
array. In this example, it would call
insert_getBanner(array("banner_id" => "12345","page_id" => "67890"));
</para>
<para>
Another thing to keep in mind for the insert tag is caching. Smarty does not
currently support caching but if we decide to implement that, insert
tags will not be cached. They will run dynamically every time the page
is created. This works good for things like banners, polls, live weather,
user feedback areas, etc.
</para>
</sect2>
<sect2>
<title>if,elseif,else</title>
<para>
if statements in Smarty have much the same flexability as php if statements,
with a few added features for the template engine.
Every if must be paired with /if. else and elseif are also permitted.
"eq", "ne","neq", "gt", "lt", "lte", "le", "gte" "ge","is even","is odd",
"is not even","is not odd","not","mod","even by","odd by","==","!=",">",
"<","<=",">=" are all valid conditional qualifiers.
</para>
<example>
<title>Template example of if statements</title>
<programlisting>
{if $name eq "Fred"}
Welcome Sir.
{elseif $name eq "Wilma"}
Welcome Ma'am.
{else}
Welcome, whatever you are.
{/if}
{* an example with "or" logic *}
{if $name eq "Fred" or $name eq "Wilma"}
...
{/if}
{* parenthesis are allowed *}
{if ( $amount < 0 or $amount > 1000 ) and $volume >= #minVolAmt#}
...
{/if}
{* you can also imbed php functionality, where appropriate *}
{if count($var) gt 0}
...
{/if}
{* test if values are even or odd *}
{if $var is even}
...
{/if}
{if $var is odd}
...
{/if}
{if $var is not odd}
...
{/if}
{* test if var is divisable by 4 *}
{if $var is mod 4}
...
{/if}
{* test if var is even, grouped by two. i.e.,
1=even, 2=even, 3=odd, 4=odd, 5=even, 6=even, etc. *}
{if $var is even by 2}
...
{/if}
</programlisting>
</example>
</sect2>
<sect2>
<title>ldelim,rdelim</title>
<para>
ldelim and rdelim are used for displaying the literal delimiter, in
our case "{" or "}". The template engine always tries to interpret
delimiters, so this is the way around that.
</para>
<example>
<title>Template example of ldelim, rdelim</title>
<programlisting>
{* this will print literal delimiters out of the template *}
{ldelim}funcname{rdelim} is how functions look in Smarty!
OUTPUT:
{funcname} is how functions look in Smarty!
</programlisting>
</example>
</sect2>
<sect2>
<title>literal</title>
<para>
Literal tags allow a block of data to be taken literally,
not being interpreted by the Smarty engine. This is handy
for things like javascript sections, where there maybe
curly braces and such things that would confuse the template
parser. Anything within {literal}{/literal} tags is not
interpreted, but displayed as-is.
</para>
<example>
<title>Template example of literal tags</title>
<programlisting>
{literal}
&lt;script language=javascript&gt;
&lt;!--
function isblank(field) {
if (field.value == '')
{ return false; }
else
{
document.loginform.submit();
return true;
}
}
// --&gt;
&lt;/script&gt;
{/literal}
</programlisting>
</example>
</sect2>
<sect2>
<title>section,sectionelse</title>
<para>
Template sections are used for looping over arrays of data.
All section tags must be paired with /section tags.
Required parameters are "name" and "loop". The name of the
section can be anything you like, made up of letters, numbers
and underscores. Sections can be nested, and the nested
section names must be unique from each other. The loop variable
determines the number of times the section will loop. sectionelse
will be used if there are no values in the loop variable.
When printing a variable within a section, the section name
must be prepended to the variable name, separated by a slash (/).
sectionelse is executed when there are no values in the loop
variable.
</para>
<example>
<title>example: section</title>
<programlisting>
{* this example will print out all the values of the $custid array *}
{section name=customer loop=$custid}
id: {$customer/custid}&lt;br&gt;
{/section}
OUTPUT:
id: 1000&lt;br&gt;
id: 1001&lt;br&gt;
id: 1002&lt;br&gt;
</programlisting>
</example>
<example>
<title>example: section loop variable</title>
<programlisting>
{* the loop variable only determines the number of times to loop.
you can access any variable from the template within the section.
This example assumes that $custid, $name and $address are all
arrays containing the same number of values *}
{section name=customer loop=$custid}
id: {$customer/custid}&lt;br&gt;
name: {$customer/name}&lt;br&gt;
address: {$customer/address}&lt;br&gt;
&lt;p&gt;
{/section}
OUTPUT:
id: 1000&lt;br&gt;
name: John Smith&lt;br&gt;
address: 253 N 45th
&lt;p&gt;
id: 1001&lt;br&gt;
name: Jack Jones&lt;br&gt;
address: 417 Mulberry ln
&lt;p&gt;
id: 1002&lt;br&gt;
name: Jane Munson
address: 5605 apple st
&lt;p&gt;
</programlisting>
</example>
<example>
<title>example: section names</title>
<programlisting>
{* the name of the section can be anything you like,
and it is used to reference the data within the section *}
{section name=mydata loop=$custid}
id: {$mydata/custid}&lt;br&gt;
name: {$mydata/name}&lt;br&gt;
address: {$mydata/address}&lt;br&gt;
&lt;p&gt;
{/section}
</programlisting>
</example>
<example>
<title>example: nested sections</title>
<programlisting>
{* sections can be nested as deep as you like. With nested sections,
you can access complex data structures, such as multi-dimensional
arrays. In this example, $customer/contact_type is an array of
contact types for the current customer. *}
{section name=customer loop=$custid}
id: {$customer/custid}&lt;br&gt;
name: {$customer/name}&lt;br&gt;
address: {$customer/address}&lt;br&gt;
{section name=contact loop=$customer/contact_type}
{$customer/contact/contact_type}: {$customer/contact/contact_info}&lt;br&gt;
{/section}
&lt;p&gt;
{/section}
OUTPUT:
id: 1000&lt;br&gt;
name: John Smith&lt;br&gt;
address: 253 N 45th
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: john@mydomain.com
&lt;p&gt;
id: 1001&lt;br&gt;
name: Jack Jones&lt;br&gt;
address: 417 Mulberry ln
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: jack@mydomain.com
&lt;p&gt;
id: 1002&lt;br&gt;
name: Jane Munson
address: 5605 apple st
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: jane@mydomain.com
&lt;p&gt;
</programlisting>
</example>
<example>
<title>example: sectionelse</title>
<programlisting>
{* sectionelse will execute in the case there are no $custid values *}
{section name=customer loop=$custid}
id: {$customer/custid}&lt;br&gt;
{sectionelse}
there are no values in $custid.
{/section}
</programlisting>
</example>
</sect2>
<sect2>
<title>strip</title>
<para>
Strip is another nice feature of the template engine. Many times
you run into the issue where white space and carriage returns
affect the output of the rendered HTML (browser "features"), so you
must run all your tags together in the template to get the
desired results. This usually ends up in unreadable or
unmanagable templates.
</para>
<para>
Anything within {strip}{/strip} tags in Smarty are stripped of
the extra spaces or carriage returns at the beginnings and
ends of the lines before they are displayed.
This way you can keep your templates readable, and not worry
about extra white space causing problems.
</para>
<example>
<title>Template example of strip tags</title>
<programlisting>
{* the following will be all run into one line upon output *}
{strip}
&lt;table border=0&gt;
&lt;tr&gt;
&lt;td&gt;
&lt;A HREF="{$url}"&gt;
&lt;font color="red"&gt;This is a test&lt;/font&gt;
&lt;/A&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
{/strip}
OUTPUT:
&lt;table border=0&gt;&lt;tr&gt;&lt;td&gt;&lt;A HREF="http://my.domain.com"&gt;&lt;font color="red"&gt;This is a test&lt;/font&gt;&lt;/A&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
</programlisting>
</example>
<para>
Notice that in the above example, all the lines begin and end
with HTML tags. Be aware that all the lines are run together.
If you have plain text at the beginning or end of any line,
they will be run together, and may not be desired results.
</para>
</sect2>
</sect1>
<sect1>
<title>Custom Functions</title>
<para>
Custom functions in Smarty work much the same as the built-in functions
syntactically. Two custom functions come bundled with Smarty. You can
also write your own.
</para>
<sect2>
<title>html_options</title>
<para>
html_options is a custom function that creates html option
lists with provided data. It takes care of which item is
selected by default as well.
</para>
<example>
<title>Template example of html_options</title>
<programlisting>
{* assume that $cust_ids, and $cust_names are arrays of values,
and $customer_id may or may not be set to a value *}
&lt;select name=customer_id&gt;
{html_options values=$cust_ids selected=$customer_id output=$cust_names}
&lt;/select&gt;
OUTPUT:
&lt;select name=customer_id&gt;
&lt;option value="1000">Joe Schmoe&lt;option&gt;
&lt;option value="1001" selected>Jack Smith&lt;option&gt;
&lt;option value="1002">Jane Johnson&lt;option&gt;
&lt;option value="1003">Charlie Brown&lt;option&gt;
&lt;/select&gt;
</programlisting>
</example>
<para>
This will create an option dropdown list using the values
of the variables supplied in the template.
</para>
</sect2>
<sect2>
<title>html_select_date</title>
<para>
html_select_date is a custom function that creates date dropdowns
for you. It can display any or all of year, month, and day. Possible
attributes are (attr name, type, default val):
</para>
<itemizedlist>
<listitem><para>prefix,string,"Date_"</para></listitem>
<listitem><para>time,timestamp,(current time)</para></listitem>
<listitem><para>start_year,int,(current year)</para></listitem>
<listitem><para>end_year int (same as start_year)</para></listitem>
<listitem><para>display_days, boolean, true</para></listitem>
<listitem><para>display_months, boolean, true</para></listitem>
<listitem><para>display_years, boolean, true</para></listitem>
<listitem><para>month_format, strftime, "%B"</para></listitem>
<listitem><para>day_format, strftime, "%02d"</para></listitem>
<listitem><para>year_as_text, boolean, true</para></listitem>
</itemizedlist>
<example>
<title>Template example of html_select_date</title>
<programlisting>
{html_select_date}
OUTPUT:
&lt;select name="Date_Month"&gt;
&lt;option value="1"&gt;January&lt;/option&gt;
&lt;option value="2"&gt;February&lt;/option&gt;
&lt;option value="3"&gt;March&lt;/option&gt;
&lt;option value="4"&gt;April&lt;/option&gt;
&lt;option value="5"&gt;May&lt;/option&gt;
&lt;option value="6"&gt;June&lt;/option&gt;
&lt;option value="7"&gt;July&lt;/option&gt;
&lt;option value="8"&gt;August&lt;/option&gt;
&lt;option value="9"&gt;September&lt;/option&gt;
&lt;option value="10"&gt;October&lt;/option&gt;
&lt;option value="11"&gt;November&lt;/option&gt;
&lt;option value="12" selected&gt;December&lt;/option&gt;
&lt;/select&gt;
&lt;select name="Date_Day"&gt;
&lt;option value="1"&gt;01&lt;/option&gt;
&lt;option value="2"&gt;02&lt;/option&gt;
&lt;option value="3"&gt;03&lt;/option&gt;
&lt;option value="4"&gt;04&lt;/option&gt;
&lt;option value="5"&gt;05&lt;/option&gt;
&lt;option value="6"&gt;06&lt;/option&gt;
&lt;option value="7"&gt;07&lt;/option&gt;
&lt;option value="8"&gt;08&lt;/option&gt;
&lt;option value="9"&gt;09&lt;/option&gt;
&lt;option value="10"&gt;10&lt;/option&gt;
&lt;option value="11"&gt;11&lt;/option&gt;
&lt;option value="12"&gt;12&lt;/option&gt;
&lt;option value="13" selected&gt;13&lt;/option&gt;
&lt;option value="14"&gt;14&lt;/option&gt;
&lt;option value="15"&gt;15&lt;/option&gt;
&lt;option value="16"&gt;16&lt;/option&gt;
&lt;option value="17"&gt;17&lt;/option&gt;
&lt;option value="18"&gt;18&lt;/option&gt;
&lt;option value="19"&gt;19&lt;/option&gt;
&lt;option value="20"&gt;20&lt;/option&gt;
&lt;option value="21"&gt;21&lt;/option&gt;
&lt;option value="22"&gt;22&lt;/option&gt;
&lt;option value="23"&gt;23&lt;/option&gt;
&lt;option value="24"&gt;24&lt;/option&gt;
&lt;option value="25"&gt;25&lt;/option&gt;
&lt;option value="26"&gt;26&lt;/option&gt;
&lt;option value="27"&gt;27&lt;/option&gt;
&lt;option value="28"&gt;28&lt;/option&gt;
&lt;option value="29"&gt;29&lt;/option&gt;
&lt;option value="30"&gt;30&lt;/option&gt;
&lt;option value="31"&gt;31&lt;/option&gt;
&lt;/select&gt;
&lt;select name="Date_Year"&gt;
&lt;option value="2001" selected&gt;2001&lt;/option&gt;
&lt;/select&gt;
</programlisting>
</example>
<example>
<title>Template example of html_select_date</title>
<programlisting>
{html_select_date prefix="StartDate" time=$time start_year=1995 end_year=2001 display_days=false}
&lt;select name="StartDateMonth"&gt;
&lt;option value="1"&gt;January&lt;/option&gt;
&lt;option value="2"&gt;February&lt;/option&gt;
&lt;option value="3"&gt;March&lt;/option&gt;
&lt;option value="4"&gt;April&lt;/option&gt;
&lt;option value="5"&gt;May&lt;/option&gt;
&lt;option value="6"&gt;June&lt;/option&gt;
&lt;option value="7"&gt;July&lt;/option&gt;
&lt;option value="8"&gt;August&lt;/option&gt;
&lt;option value="9"&gt;September&lt;/option&gt;
&lt;option value="10"&gt;October&lt;/option&gt;
&lt;option value="11"&gt;November&lt;/option&gt;
&lt;option value="12" selected&gt;December&lt;/option&gt;
&lt;/select&gt;
&lt;select name="StartDateYear"&gt;
&lt;option value="1999"&gt;1995&lt;/option&gt;
&lt;option value="1999"&gt;1996&lt;/option&gt;
&lt;option value="1999"&gt;1997&lt;/option&gt;
&lt;option value="1999"&gt;1998&lt;/option&gt;
&lt;option value="1999"&gt;1999&lt;/option&gt;
&lt;option value="2000" selected&gt;2000&lt;/option&gt;
&lt;option value="2001"&gt;2001&lt;/option&gt;
&lt;/select&gt;
</programlisting>
</example>
</sect2>
<sect2>
<title>Creating your own Custom Functions</title>
<para>
Creating your own functions is a fairly straight forward process.
The best way is to look at the ones that come with Smarty as
examples. The function names begin with smarty_func_ and they are
located in the Smarty.addons.php file.
</para>
<itemizedlist>
<listitem><para>add your function to the Smarty.addons.php file.
It is recommended that you prepend your function name
with smarty_func_</para></listitem>
<listitem><para>map a template function name to your PHP function.
This is done at the top of the Smarty.class.php file
in the $custom_funcs array.</para></listitem>
<listitem><para>Thats it! you can now call that function
from within Smarty.</para></listitem>
</itemizedlist>
<para>
All attributes passed to custom functions are passed into the
first argument as an indexed array. One way to get to those
values is to call extract(func_get_arg(0)); at the top of your
function. Anything that the function returns gets displayed
in place of the tag in the template.
</para>
</sect2>
</sect1>
<sect1>
<title>Variable Modifiers</title>
<para>
Variable modifiers are a bit different than custom functions.
They do just what they sound like, they modify variables before
they are displayed to the template. The best way to explain
these are by example.
</para>
<example>
<title>Template example of variable modifiers</title>
<programlisting>
{* this displays a variable, unmodified *}
{$articleTitle}
OUTPUT:
Burger King fire leaves seven pregnant teenagers &lt;jobless&gt;
{* this displays the variable in all upper case *}
{$articleTitle|upper}
OUTPUT:
BURGER KING FIRE LEAVES SEVEN PREGNANT TEENAGERS &lt;JOBLESS&gt;
{* this displays the variable html escaped *}
{$articleTitle|escape}
OUTPUT:
Burger King fire leaves seven pregnant teenagers &amp;lt;jobless&amp;gt;
{* this displays the variable uppercased AND html escaped *}
{$articleTitle|upper|escape}
OUTPUT:
BURGER KING FIRE LEAVES SEVEN PREGNANT TEENAGERS &amp;lt;JOBLESS&amp;gt;
{* an example of passing a parameter to a modifier:
this displays the variable url escaped *}
{$articleTitle|escape:"url"}
OUTPUT:
Burger+King+fire+leaves+seven+pregnant+teenagers+%3Cjobless%3e
{* print the first 24 characters of this variable, and
follow with ... if it was longer *}
{$articleTitle|truncate:24:"..."}
OUTPUT:
Burger King fire...
{* print the date in default format *}
{$startTime|date_format}
OUTPUT:
Dec 13, 2000
{* print the hour, minute and second portion of a date *}
{$startTime|date_format:"%h:%m:%s"}
OUTPUT:
10:33:02
{* print a number to the first two decimals *}
{$amount|string_format:"%.2f"}
OUTPUT:
24.02
</programlisting>
</example>
<para>
All modifiers will get the value of the variable as the first argument,
and must return a single value. Modifier parameters are separated by colons.
Any additional parameters passed to a modifier are passed as-is positionally,
much like calling a PHP function. You can also use native
PHP functions as modifiers, but only if they expect the correct
arguments. If they do not, you can always write a wrapper function
in Smarty to get what you want (date_format is a wrapper function
to strftime() for example.) You can chain as many modifiers
together on a variable as you like, separating each with a vertical
pipe "|".
</para>
<para>
NOTE: if you apply a modifier to an array
instead of a single value variable, the modifier will be applied to every
value in that array. If you really want the entire array passed
to the modifier, you must prepend it with an "@" sign like so:
{$articleTitle|@count} (this will print out the number of elements
in the $articleTitle array.)
</para>
<sect2>
<title>captialize</title>
<para>
This is used to capitalize the first letter of all words in a variable.
</para>
</sect2>
<sect2>
<title>date_format</title>
<para>
This formats a date into the given strftime() format. All dates
should be passed to Smarty as a timestamp so that the template
designer has full control of how this date is formatted. The
default format is "%b %e, %Y", or "Jan 4, 2001" for example.
These are the possible conversion specifiers:
</para>
<example>
<title>date_format conversion specifiers</title>
<programlisting>
%a - abbreviated weekday name according to the current locale
%A - full weekday name according to the current locale
%b - abbreviated month name according to the current locale
%B - full month name according to the current locale
%c - preferred date and time representation for the current locale
%C - century number (the year divided by 100 and truncated to an integer, range 00 to 99)
%d - day of the month as a decimal number (range 00 to 31)
%D - same as %m/%d/%y
%e - day of the month as a decimal number, a single digit is preceded by a space (range ' 1' to '31')
%h - same as %b
%H - hour as a decimal number using a 24-hour clock (range 00 to 23)
%I - hour as a decimal number using a 12-hour clock (range 01 to 12)
%j - day of the year as a decimal number (range 001 to 366)
%m - month as a decimal number (range 01 to 12)
%M - minute as a decimal number
%n - newline character
%p - either `am' or `pm' according to the given time value, or the corresponding strings for the current locale
%r - time in a.m. and p.m. notation
%R - time in 24 hour notation
%S - second as a decimal number
%t - tab character
%T - current time, equal to %H:%M:%S
%u - weekday as a decimal number [1,7], with 1 representing Monday
%U - week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week
%V - The ISO 8601:1988 week number of the current year as a decimal number, range 01 to 53, where week 1
is the first week that has at least 4 days in the current year, and with Monday as the first day of the week.
%W - week number of the current year as a decimal number, starting with the first Monday as the first day of the first week
%w - day of the week as a decimal, Sunday being 0
%x - preferred date representation for the current locale without the time
%X - preferred time representation for the current locale without the date
%y - year as a decimal number without a century (range 00 to 99)
%Y - year as a decimal number including the century
%Z - time zone or name or abbreviation
%% - a literal `%' character
</programlisting>
</example>
</sect2>
<sect2>
<title>escape</title>
<para>
This is used to html or url escape a variable. By default,
the variable is html escaped. possible arguments are "url" or "html".
</para>
</sect2>
<sect2>
<title>lower</title>
<para>
This is used to lowercase a variable.
</para>
</sect2>
<sect2>
<title>replace</title>
<para>
A simple search and replace on a variable. The first argument is
what to search for, the second argument is what to replace it with.
</para>
</sect2>
<sect2>
<title>spacify</title>
<para>
spacify is a way to insert spaces between every character of a variable.
You can optionally pass a different character (or string) to insert.
</para>
</sect2>
<sect2>
<title>string_format</title>
<para>
This is a way to format strings, such as decimal numbers and such.
Use the syntax for sprintf for the formatting.
</para>
</sect2>
<sect2>
<title>strip_tags</title>
<para>
This strips out markup tags, basically anything between &lt; and &gt;.
</para>
</sect2>
<sect2>
<title>truncate</title>
<para>
This truncates a variable to a character length, default is 80. As
an optional second parameter, you can specify a string of text
to display at the end if the variable was indeed truncated. The
characters in the string are included with the original truncation length.
By default, truncate will attempt to cut off at a word boundary. If
you want to cut off at the exact character length, pass the optional
third parameter of true.
</para>
</sect2>
<sect2>
<title>upper</title>
<para>
This is used to uppercase a variable.
</para>
</sect2>
<sect2>
<title>Creating your own Variable Modifiers</title>
<para>
Creating your own modifiers is a fairly straight forward process.
The best way is to look at the ones that come with Smarty as
examples. The function names begin with smarty_mod_ and they are
located in the Smarty.addons.php file.
</para>
<itemizedlist>
<listitem><para>add your modifier to the Smarty.addons.php file.
It is recommended that you prepend your function name
with smarty_mod_</para></listitem>
<listitem><para>map a template modifier name to your PHP function.
This is done at the top of the Smarty.class.php file
in the $custom_mods array.</para></listitem>
<listitem><para>Thats it! you can now use that modifier
from within Smarty.</para></listitem>
</itemizedlist>
</sect2>
</sect1>
</chapter>
<chapter>
<title>Troubleshooting</title>
<para></para>
<sect1>
<title>Smarty/PHP errors</title>
<para>
As of now, Smarty is not a validating template parser. This means that
the parser will blindly convert the template to PHP scripts, irregardless
of any syntax errors in the markup tags that may be present in the template.
These types of errors can end up in PHP run-time errors.
When you encounter a PHP error when attempting to display the
template in a browser, the error line number will correspond to the
compiled PHP template, not the template itself. This may be a bit confusing
or for the template designer. Our experience is to tell the
designers to check their work often, and ask the programmers for help
if they are really stuck. Usually you can look at the template and spot the
syntax error. Maybe you left a delimeter off, or you didn't properly close
an {if}{/if} or {section}{/section} tag. If you can't find it, you must open
the compiled PHP file and go to the line number to figure out what went wrong.
</para>
</sect1>
</chapter>
<chapter>
<title>Syntax Highlighting in editors</title>
<para>
We have created some syntax highlighting for Nedit, a freely downloadable
text editor for X windows. You can find the files and instructions on the
Smarty web site.
</para>
</chapter>
<chapter>
<title>FAQ</title>
<para></para>
</chapter>
</book>