MVC是目前常用的開發架構，基於MVC模式的php開發框架種類繁多，但其原理大同小異。下面粗略的講解一下MVC中的URL解析過程。
衆所周知，MVC架構往往採用單一文件入口，通過URL地址映射，調用相應的controller,model,view完成業務邏輯和頁面顯示。爲了對搜索引擎友好，URL地址往往寫成這樣：http://localhost/web/action/method/id/1
或者http://localhost/web/action/method/id/1.shtml的形式，即，調用web下的action類中的 method方法，參數是id=1。如何從URL中分離這些類，方法和參數呢？這就需要寫一個URL解析類(class.route.php)，URL解析完成後，需要調用相應的類完成任務，所以還需要一個分發類(class.dispatcher.php)，不要忘了，還有入口文件和配置文件。
一、配置文件：config.php
爲了簡單起見，我們只配置一下url的僞靜態後綴。
<?php
return array(
'HTML_URL_SUFFIX'=>'.shtml' //僞靜態後綴shtml,html,htm都可以
);
?>
二、.htaccess文件：過濾掉index.php
# Turn on URL rewriting
RewriteEngine On
# Installation directory 如果你的項目在非根目錄的話，就填目錄名，比如：/test/
RewriteBase /urltest/
# Protect application and system files from being viewed
RewriteRule ^(application|modules|system) - [F,L]
# Allow any files or directories that exist to be displayed directly
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
# Rewrite all other URLs to index.php/URL
RewriteRule .* index.php/$0 [PT,L]
# or
#RewriteRule .* index.php?arg=$0 [PT,L]
三、入口文件:index.php
<?php
require 'class.route.php';
require 'class.dispacher.php';
$route = new Route();
$dis = new Dispatcher($route);
$dis->dispatch();
?>
四、Route類：用於解析URL
<?php
class Route{
private $action;
private $method;
private $params = array();
public function __construct(){
$this->parseURL();
}
public function __get($name){
return $name;
}
//URL解析
public function parseURL(){
$str1 = $_SERVER['PHP_SELF'];
$str2 = $_SERVER['SCRIPT_NAME'];
$len = strlen($str2);
$des = substr($str1,$len+1,strlen($str1));
$config = require("config.php");
if($suffix = $config['HTML_URL_SUFFIX'])
$des = substr($des,0,strlen($des)-strlen($suffix));
//分別取出action,method,id,1
$arr = explode("/",$des);
$this->action = array_shift($arr);
$this->method = array_shift($arr);
$this->params = array(); //參數數組params[參數名稱]=參數值
for($i=0;$i<count($arr);$i=$i+2){
$this->params[$arr[$i]] = $arr[$i+1];
}
}
public function getAction(){
return $this->action;
}
public function getMethod(){
return $this->method;
}
public function getParams(){
return $this->params;
}
}
?>
五、Dispatcher類：調用解析出來的類和方法，完成業務邏輯
<?php
class Dispatcher{
private $route = NULL;
private $action;
private $method;
private $params = array();
public function __construct($route){
$this->route = $route;
$this->action = $route->getAction();
$this->method = $route->getMethod();
$this->params = $route->getParams();
}
public function dispatch(){
//加載action類,method方法
if(empty($this->action))
$this->action="Index";
if(empty($this->method))
$this->method = "index";
if(!file_exists($this->action."Action.php"))
echo "{$this->action}Action not found!";
else{
require($this->action."Action.php");
$className = $this->action."Action";
$action = new $className();
$method = $this->method;
if(!method_exists($action,$this->method))
echo "{$method}() not found";
else
$action->$method($this->params);
}
}
}
?>
六、測試的action類：IndexAction包含inde()方法,用於默認訪問
<?php
class IndexAction{
public function index($arr){
echo "<pre>";
print_r($arr);
echo "</pre>";
echo "Hello,world!";
}
}
?>
程序的執行過程是這樣的：用戶輸入http://localhost/web/Index/index/id/1，index.php文件接 收，調用route解析URL地址，dispatcher通過解析結果調用相應的action和method。過程是不是很簡單呢，此文只爲抱磚引玉，簡 述原理。讀者可根據自己的需要，根據原理架構自己的MVC框架。
