Caterpillar teaches you to write your own template engine_PHP tutorial

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Smarty一直被人视为是多余的东西，我觉得认为Smarty多余的人才是多余的....不说这些了。今天我就教大家写个模板引擎，让大家都可以写一个属于自己的模板引擎，而且看完这篇文章之后，你对Smarty的认识会更进一步的。我的模板引擎名叫Stupid（"傻瓜"的意思），我不喜欢太聪明的东西！
Stupid模板引擎是由3个文件组成，他们分别是：stupid.class.php，stupid_parser.class.php，stupid_debugger.class.php。
Stupid.class.php的任务是设置变量，模板路径，和显示等功能，而stupid_parser.class.php就是编译模板文件的，stupid_debugger.class.php是用来调试用的。

好了，我们现在就先编写stupid.class.php吧。
1.新建一个PHP文件名为：stupid.class.php。
我们的类叫Stupid，我们先设计一下成员变量吧。
成员变量有：$_tpl_vars, $_tpl_file, $_parser, $_debugger;
$_tpl_vars: 用来保存模板变量的;
$_tpl_file: 用来保存模板文件名的;
$_parser: 保存StupidParser对象的,就是编译对象;
$_debugger: 保存StupidDebug对象的,就是调试对象;

下面定义了两个常量，用来存放模板文件夹和编译文件夹的：
define(TPL_DIR, ./templates/);
define(TPL_C_DIR, ./templates_c/);

开始编码了>>>

define(TPL_DIR, ./templates/);
define(TPL_C_DIR, ./templates_c/);

class Stupid {
        private $_tpl_vars;
        private $_tpl_file;
        private $_parser;
        private $_debugger;
}
?>

开始写个构造器吧>>>

public function Stupid() {
  if(!is_dir(TPL_DIR) || !is_dir(TPL_C_DIR)) {
   exit(错误：请正确设置模板文件夹和编译文件夹);
  }
}

在构造器中,我们判断了模板路径和编译路径是否设置正确.

设计我们的方法
我们这个类中主要有以下方法:
assign(), set_tpl_dir(), set_parsed_dir(), display(), debug().
assign()方法:
assign()的用处是设置模板变量.代码如下>>>

public function assign($var, $value) {
if(isset($var) && trim($var) != ) {
                $this->_tpl_vars[$var] = $value;
                return true;
        } else {
                exit(错误：请设置变量名);
        }
}
我们先判断用户是否设置了变量名,用isset($var) && trim($var) != 来判断, trim($var) != 是防止用户以空格来设置变量名.如果设置变量正确,我们就将他保存到成员变量_tpl_vars中.

display()方法
display()方法是Stupid类中最重要的方法,他是用来显示和检测模板是否更新了,更新了就再编译,没有更新就用原来编译之后的文件.

代码如下>>>

public function display($tpl_file) {
  $template_file = TPL_DIR.$tpl_file;
  if(!file_exists($template_file)) {
   exit(错误：模板文件不存在);
  }
 
  $parsed_file = TPL_C_DIR.md5($tpl_file)..php;
  if(!file_exists($parsed_file) || filemtime($parsed_file)    require_once ./stupid_parser.class.php;
   $this->_parser = new StupidParser();
   $this->_parser->compile($tpl_file);
  }
  include $parsed_file;
}

这个方法是根据!file_exists($parsed_file)||filemtime($parsed_file)

debug()方法
Debugg()方法就比较简单,就是引入stupid_debugger.class.php文件,创建StupidDebuger对象,调用StupidDebuger的start方法进行调试.

代码如下>>>

public function debug ($tpl_file) {
if (include_once("stupid_debugger.class.php")) {
$this->_debugger = new StupidDebugger(TPL_DIR. $tpl_file);
$ this-& gt; _debugger-& gt; start ();
} Else {
EXIT (error: Debuger file does not exist);
At this point, our Stupid class is finished! Next time I will introduce the writing of the StupidParser class. Please continue to support. If you have any comments or suggestions, please feel free to put forward!

show show full photo:

define(TPL_DIR, ./templates/);

define(TPL_C_DIR, ./templates_c/);

class Stupid {
private $_tpl_vars;
private $_tpl_file;
private $_parser;
private $_debug;

public function Stupid() {
if(!is_dir(TPL_DIR) || !is_dir(TPL_C_DIR)) {

exit(Error: Please set the template folder and compilation folder correctly);

}
}

public function assign($var, $value) {
if(isset($var) && trim($var) != ) {

$this->_tpl_vars[$var] = $value ;

return true;
} else {
exit(Error: Please set variable name);
}
}

public function display($tpl_file) {
$template_file = TPL_DIR.$tpl_file;

if(!file_exists($template_file)) {

exit(Error: template file does not exist);
}

$parsed_file = TPL_C_DIR.md5($tpl_file)..php;
if(!file_exists($parsed_file) || filemtime($parsed_file) require_once ./stupid_parser.class.php;
$this->_parser = new StupidParser();
$this->_parser->compile($tpl_file);
}
include $parsed_file;
}

function debug($tpl_file) {
if (include_once("stupid_debugger.class.php")) {

$this->_debugger = new StupidDebugger($this->_template_dir . $tpl_file) ;

$this->_debugger->start();
} else {
exit(Error: Debuger class file does not exist);
}
}
}
?>

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www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/486612.htmlTechArticle#phpchina开户# Smarty has always been regarded as redundant. I think people who think Smarty is redundant are redundant. .... Let’s not talk about this anymore. Today I will teach you how to write a template engine so that you can...