PHP 自动加载对象（以MVC框架为例）
1, 在程序使用未声明的类时会自动调用 __autolaod() 函数来加载;
2.其中 spl_autoload_register() 用来注册一个自动调用的函数, 可以注册多个函数!
3.$iniPath = ini_get('include_path');ini_set('include_path', $iniPath. . $cPath);通过设置环境变量来达到autoload目的，设置包含路径，以后可以直接包含这些目录中的文件，不需要再写详细的路径了。方法三取自php.MVC,使用参照php.MVC文档
Setup the application class paths (PHP 'include_path') for the included * class files, for the duration of the main script * *?Returns the class path string for testing purposes * * @depreciated * @param string The appServerRootDir. eg: 'C:/Www/phpmvc' * @param array An array of sub-application paths,
* eg: $subAppPaths[] = 'WEB-INF/classes/example';, ... * @param string The OS [Optional] [UNIX|WINDOWS|MAC|...] if we have * trouble detecting the server OS type. Eg: path errors. * @public * @returns string */ function setClassPath($appServerRootDir='', $subAppPaths='', $osType='') { // Set AppServer root manually for now if($appServerRootDir == '') { echo 'Error: ClassPath :- No php.MVC application root directory specified'; exit; } #$_ENV; // PHP Superglobals !! // Setup the main phpmvc application include() directories here // Note: could be placed in a n xml config file later !! $appDirs = array(); $appDirs[] = ''; // application root directory $appDirs[] = 'lib'; // Add the sub-application paths, if any if(is_array($subAppPaths)) { $appDirs = array_merge($appDirs, $subAppPaths); } // Setup the platform specific path delimiter character $delim = NULL; // path delimiter character. (Windows, Unix, Mac!!) $winDir = NULL; if( (int)phpversion() > 4 ) { // PHP 5 $winDir = $_ENV["windir"]; // See: PHP v.4.1.0 Superglobals } else { // PHP 4 global $HTTP_ENV_VARS; // depreciated- if( array_key_exists("windir", $HTTP_ENV_VARS) ) { $winDir = $HTTP_ENV_VARS["windir"]; // will be replaced with $_ENV } } if($osType != '') { if( eregi("WINDOWS", $osType) ) { $delim = ';'; // Windows } elseif( eregi("UNIX", $osType) ) { $delim = ':'; // Unix } elseif( eregi("MAC", $osType) ) { $delim = ':'; // Mac !!!!! } } if($delim == NULL) { if( eregi("WIN", $winDir) ) { // _ENV["C:\Win2K"] $delim = ';'; // Windows } else { $delim = ':'; // Unix, Mac !! } } // Get the current working directory $path = $appServerRootDir; // Strip path directories below 'WEB-INF' $pathToWebInf = ereg_replace("WEB-INF.*$", '', $path); // Replace path backslashes with forward slashes // Note: PHP Regular Expressions do not work with backslashes $pathToWebInf = str_replace("\", "/", $pathToWebInf); // Drop the trailing slash, if one is present $pathToWebInf = ereg_replace("/$", '', $pathToWebInf); // Setup the environment path string $classPath = NULL; foreach($appDirs as $appDir) { $classPath .= $pathToWebInf.'/'.$appDir.$delim; } // Remove trailing delimiter character $classPath = substr($classPath, 0, -1); // Setup the include_path for the duration of the main php.MVC script ini_set('include_path', $classPath); return $classPath; // for testing } // ----- Public Methods ------------------------------------------------- // function getClassPath($appServerRootDir='', $appDirs, $osType='') { // Set AppServer root manually for now if($appServerRootDir == '') { echo 'Error: ClassPath :- No php.MVC application root directory specified'; exit; } #$_ENV; // PHP Superglobals !! // Setup the platform specific path delimiter character $delim = NULL; // path delimiter character. (Windows, Unix, Mac!!) if($osType == '') { // PHP's build in constant "PATH_SEPARATOR" [unix (:) / win (;)] $delim = PATH_SEPARATOR; } else { // It is handy to be able to specift the OS type for testing $delim = ClassPath::getPathDelimiter($osType); } // Get the current working directory $path = $appServerRootDir; // Strip path directories below 'WEB-INF' $pathToWebInf = ereg_replace("WEB-INF.*$", '', $path); // Replace path backslashes with forward slashes // Note: PHP Regular Expressions do not work with backslashes $pathToWebInf = str_replace("\", "/", $pathToWebInf); // Drop the trailing slash, if one is present $pathToWebInf = ereg_replace("/$", '', $pathToWebInf); // Setup the environment path string $classPath = NULL; $AbsolutePath = False; // Say: "/Some/Unix/Path/" or "D:\Some\Win\Path" foreach($appDirs as $appDir) { // Check if the specified system path is an absolute path. Absolute system // paths start with a "/" on Unix, and "Ch\:" or "Ch/:" on Win 32. // Eg: "/Some/Unix/Path/" or "D:\Some\Win\Path" or "D:/Some/Win/Path". $AbsolutePath = ClassPath::absolutePath($appDir); if($AbsolutePath == True) { $classPath .= $appDir.$delim; } else { $classPath .= $pathToWebInf.'/'.$appDir.$delim; } } // Remove trailing delimiter character $classPath = substr($classPath, 0, -1); return $classPath; // for testing } /** * Concatenate environment path strings ** Returns the two path strings joined with the correct environment * string delimiter for the host operating system. * * @param string The path string * @param string The path string * @param string The operating type [optional] * @public * @returns string */ function concatPaths($path1, $path2, $osType='') { // Setup the platform specific path delimiter character $delim = NULL; // path delimiter character. (Windows, Unix, Mac!!) $delim = ClassPath::getPathDelimiter($osType); $path = $path1 . $delim . $path2; return $path; } // ----- Protected Methods ---------------------------------------------- // /** * Get environment path delimiter. *
* Returns the environment string delimiter for the host operating system. * * @param string The operating type [optional] * @protected * @returns string */ function getPathDelimiter($osType='') { // Setup the platform specific path delimiter character $delim = NULL; // path delimiter character. (Windows, Unix, Mac!!) $winDir = NULL; if( (int)phpversion() > 4 ) { // PHP 5 $winDir = $_ENV["windir"]; // See: PHP v.4.1.0 Superglobals } else { // PHP 4 global $HTTP_ENV_VARS; // depreciated- if( array_key_exists("windir", $HTTP_ENV_VARS) ) { $winDir = $HTTP_ENV_VARS["windir"]; // will be replaced with $_ENV } } if($osType != '') { if( eregi("WINDOWS", $osType) ) { $delim = ';'; // Windows } elseif( eregi("UNIX", $osType) ) { $delim = ':'; // Unix } elseif( eregi("MAC", $osType) ) { $delim = ':'; // Mac !!!!! } } if($delim == NULL) { if( eregi("WIN", $winDir) ) { // _ENV["C:\Win2K"] $delim = ';'; // Windows } else { $delim = ':'; // Unix, Mac !! } } return $delim; } /** * Check if the specified system path is an absolute path. Absolute system * paths start with a "/" on Unix, and "Ch\:" or "Ch/:" on Win 32. * Eg: "/Some/Unix/Path/" or "D:\Some\Win\Path" or "D:/Some/Win/Path". * * Returns True if the suppplied path absolute, otherwise returns False * * @param string The path to check, like: "/Some/Unix/Path/" or * "D:\Some\Win\Path". * @public * @returns boolean */ function absolutePath($systemPath) { // Say: "/Some/Unix/Path/" or "D:\Some\Win\Path" or "D:/Some/Win/Path" $fAbsolutePath = False; // Boolean flag value //"[/]Some/Unix/Path/" if (preg_match("/^\//", $systemPath)) { $fAbsolutePath = True; //"[D:\]Some\Win\Path" // "i" says "ignore case" // Note the extra escape "\" reqd for this to work with PHP !!! } elseif(preg_match("/^[a-z]:\\/i", $systemPath)) { $fAbsolutePath = True; //"[D:/]Some/Win/Path" } elseif(preg_match("/^[a-z]:\//i", $systemPath)) { $fAbsolutePath = True; } return $fAbsolutePath; }}?>
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?调用方法autoloader.php
