PHP记事（2）

继续对phpSayTemplateParser类的分析。

phpSayTemplateParser类最重要的函数就是compile()，该函数将HTML模板文件中的特定标签替换成相应的PHP代码，如上文所述。

首先以login页面为例进行分析。

简单的部分略去不说，如：

$page = str_replace(array("/r","/n","/t"),"",$this->template);
$page = preg_replace('//s+/',' ',$page);
$page = preg_replace('/ +/',' ',$page);
$page = preg_replace("/<!-- ENDIF.+?-->/","<?php/n}/n?>",$page);
...
$page = str_replace("<!-- ELSE -->","<?php/n} else {/n?>",$page);

因为login.html中只有<!-- IF loginResult == "ok" -->，所以能实验到的只有如下代码块：

if (preg_match_all('/<!-- (ELSE)?IF ([a-zA-Z0-9_.]+)[ ]*([!=<>]+)[ ]*(["]?[^"]*["]?) -->/', $page, $var))
{
//echo "if is found";
foreach ($var[2] as $cnt => $tag)
{
list($parent, $block)  =  $this->var_name($tag);
$cmp   =  $var[3][$cnt];
$val   =  $var[4][$cnt];
$else  =  ($var[1][$cnt] == 'ELSE') ? '} else' : '';
if ($cmp == '=')
{
$cmp  =  '==';
}
if (preg_match('/"([^"]*)"/',$val,$matches))
{
$code  =  "<?php/n$else"."if (/$parent"."['$block'] $cmp /"".$matches[1]."/"){/n?>";
}
elseif (preg_match('/([^"]*)/',$val,$matches))
{
list($parent_right, $block_right)  =  $this->var_name($matches[1]);
$code  =  "<?php/n$else"."if (/$parent"."['$block'] $cmp /$parent_right"."['$block_right']){/n?>";
}
$page  =  str_replace($var[0][$cnt],  $code,  $page);
}
}

该段代码将$page字符串中所有匹配正则表达式的字符都存放入$var数组中，通过variable_inspector.php中的var_log函数将该数组输出到一个txt中（如果输入到HTML中，将不能正常显示其内容，所以一定要放到纯文本里面才行）。

通过添加代码：

if ($h_v  =  fopen("vincent.util/var.txt",  "w"))
{
fwrite($h_v,  var_log($var));
fclose($h_v);
}
foreach ($var[2] as $cnt => $tag)
{
list($parent, $block)  =  $this->var_name($tag);
if ($h_v  =  fopen("vincent.util/var.txt",  "a"))
{
fwrite($h_v,  var_log($parent));
fwrite($h_v,  var_log($block));
fclose($h_v);
}
$cmp   =  $var[3][$cnt];
$val   =  $var[4][$cnt];
$else  =  ($var[1][$cnt] == 'ELSE') ? '} else' : '';

内容为：

= Array (

| 0 = Array (

| | 0 = "<!-- IF loginResult == "ok" -->"

| | 1 = "<!-- IF loginResult == "error" -->"

| | 2 = "<!-- IF loginResult == "ok" -->"

| )

| 1 = Array (

| | 0 = ""

| | 1 = ""

| | 2 = ""

| )

| 2 = Array (

| | 0 = "loginResult"

| | 1 = "loginResult"

| | 2 = "loginResult"

| )

| 3 = Array (

| | 0 = "=="

| | 1 = "=="

| | 2 = "=="

| )

| 4 = Array (

| | 0 = ""ok""

| | 1 = ""error""

| | 2 = ""ok""

| )

)

= "_obj"
= "loginResult"
= "_obj"
= "loginResult"
= "_obj"
= "loginResult"

至于正则表达式'/<!-- (ELSE)?IF ([a-zA-Z0-9_.]+)[ ]*([!=<>]+)[ ]*(["]?[^"]*["]?) -->/'，需要另外新开一个文件进行实验。