CodeIgniter.php 引入的第六个核心文件($RTR),在Uri文件中也有被引用。启用路由功能,设置自己的路由规则。
这一段理解的不够好,需要反复阅读。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2014 - 2015, British Columbia Institute of Technology
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* @package CodeIgniter
* @author EllisLab Dev Team
* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
* @copyright Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
* @license http://opensource.org/licenses/MIT MIT License
* @link http://codeigniter.com
* @since Version 1.0.0
* @filesource
*/
defined('BASEPATH') OR exit('No direct script access allowed');

/**
* Router Class
*
* Parses URIs and determines routing
*
* @package CodeIgniter
* @subpackage Libraries
* @category Libraries
* @author EllisLab Dev Team
* @link http://codeigniter.com/user_guide/general/routing.html
*/
class CI_Router {

/**
* CI_Config class object
*
* @var object
*/
public $config;

/**
* List of routes
*
* @var array
*/
public $routes = array();

/**
* Current class name
*
* @var string
*/
public $class = '';

/**
* Current method name
*
* @var string
*/
public $method = 'index';

/**
* Sub-directory that contains the requested controller class
*
* @var string
*/
public $directory;

/**
* Default controller (and method if specific)
*
* @var string
*/
public $default_controller;

/**
* Translate URI dashes
*
* Determines whether dashes in controller & method segments
* should be automatically replaced by underscores.
*
* @var bool
*/
public $translate_uri_dashes = FALSE;

/**
* Enable query strings flag
*
* Determines whether to use GET parameters or segment URIs
*
* @var bool
*/
public $enable_query_strings = FALSE;

// --------------------------------------------------------------------

/**
* Class constructor
*
* Runs the route mapping function.
*
* @return void
*/
public function __construct($routing = NULL)
{
$this->config =& load_class('Config', 'core');
$this->uri =& load_class('URI', 'core');

$this->enable_query_strings = ( ! is_cli() && $this->config->item('enable_query_strings') === TRUE);

// If a directory override is configured, it has to be set before any dynamic routing logic
is_array($routing) && isset($routing['directory']) && $this->set_directory($routing['directory']);
$this->_set_routing();

// Set any routing overrides that may exist in the main index file
if (is_array($routing))
{
empty($routing['controller']) OR $this->set_class($routing['controller']);
empty($routing['function']) OR $this->set_method($routing['function']);
}

log_message('info', 'Router Class Initialized');
}

// --------------------------------------------------------------------

/**
* Set route mapping
*
* Determines what should be served based on the URI request,
* as well as any "routes" that have been set in the routing config file.
* 初始化路由配置
*
* @return void
*/
protected function _set_routing()
{
// Load the routes.php file. It would be great if we could
// skip this for enable_query_strings = TRUE, but then
// default_controller would be empty ...
if (file_exists(APPPATH.'config/routes.php'))
{
include(APPPATH.'config/routes.php');
}

if (file_exists(APPPATH.'config/'.ENVIRONMENT.'/routes.php'))
{
include(APPPATH.'config/'.ENVIRONMENT.'/routes.php');
}

// Validate & get reserved routes
if (isset($route) && is_array($route))
{
isset($route['default_controller']) && $this->default_controller = $route['default_controller'];
isset($route['translate_uri_dashes']) && $this->translate_uri_dashes = $route['translate_uri_dashes'];
unset($route['default_controller'], $route['translate_uri_dashes']);
$this->routes = $route;
}

// 启用 ?c=cc&d=aaa& 形式访问
// Are query strings enabled in the config file? Normally CI doesn't utilize query strings
// since URI segments are more search-engine friendly, but they can optionally be used.
// If this feature is enabled, we will gather the directory/class/method a little differently
if ($this->enable_query_strings)
{
// If the directory is set at this time, it means an override exists, so skip the checks
if ( ! isset($this->directory))
{
$_d = $this->config->item('directory_trigger');
$_d = isset($_GET[$_d]) ? trim($_GET[$_d], " \t\n\r\0\x0B/") : '';

if ($_d !== '')
{
$this->uri->filter_uri($_d);
$this->set_directory($_d);
}
}

$_c = trim($this->config->item('controller_trigger'));
if ( ! empty($_GET[$_c]))
{
$this->uri->filter_uri($_GET[$_c]);
$this->set_class($_GET[$_c]);

$_f = trim($this->config->item('function_trigger'));
if ( ! empty($_GET[$_f]))
{
$this->uri->filter_uri($_GET[$_f]);
$this->set_method($_GET[$_f]);
}

$this->uri->rsegments = array(
1 => $this->class,
2 => $this->method
);
}
else
{
//默认路由。
$this->_set_default_controller();
}

// Routing rules don't apply to query strings and we don't need to detect
// directories, so we're done here
return;
}

// Is there anything to parse?
// 解析路由
if ($this->uri->uri_string !== '')
{
$this->_parse_routes();
}
else
{
$this->_set_default_controller();
}
}

// --------------------------------------------------------------------

/**
* Set request route
*
* Takes an array of URI segments as input and sets the class/method
* to be called.
*
* @used-by CI_Router::_parse_routes()
* @param array $segments URI segments
* @return void
*/
protected function _set_request($segments = array())
{
//验证是否有效。
$segments = $this->_validate_request($segments);

// If we don't have any segments left - try the default controller;
// WARNING: Directories get shifted out of the segments array!
if (empty($segments))
{
$this->_set_default_controller();
return;
}

if ($this->translate_uri_dashes === TRUE)
{
$segments[0] = str_replace('-', '_', $segments[0]);
if (isset($segments[1]))
{
$segments[1] = str_replace('-', '_', $segments[1]);
}
}

$this->set_class($segments[0]);
if (isset($segments[1]))
{
$this->set_method($segments[1]);
}
else
{
$segments[1] = 'index';
}

array_unshift($segments, NULL);
unset($segments[0]);
$this->uri->rsegments = $segments;
}

// --------------------------------------------------------------------

/**
* Set default controller
*
* @return void
*/
protected function _set_default_controller()
{
if (empty($this->default_controller))
{
show_error('Unable to determine what should be displayed. A default route has not been specified in the routing file.');
}

// Is the method being specified?
if (sscanf($this->default_controller, '%[^/]/%s', $class, $method) !== 2)
{
$method = 'index';
}

if ( ! file_exists(APPPATH.'controllers/'.$this->directory.ucfirst($class).'.php'))
{
// This will trigger 404 later
return;
}

$this->set_class($class);
$this->set_method($method);

// Assign routed segments, index starting from 1
$this->uri->rsegments = array(
1 => $class,
2 => $method
);

log_message('debug', 'No URI present. Default controller set.');
}

// --------------------------------------------------------------------

/**
* Validate request
*
* Attempts validate the URI request and determine the controller path.
*
* @used-by CI_Router::_set_request()
* @param array $segments URI segments
* @return mixed URI segments
*/
protected function _validate_request($segments)
{
$c = count($segments);
$directory_override = isset($this->directory);

// Loop through our segments and return as soon as a controller
// is found or when such a directory doesn't exist
while ($c-- > 0)
{
$test = $this->directory
.ucfirst($this->translate_uri_dashes === TRUE ? str_replace('-', '_', $segments[0]) : $segments[0]);

//默认类库不存在并且重写了 directory
if ( ! file_exists(APPPATH.'controllers/'.$test.'.php')
&& $directory_override === FALSE
&& is_dir(APPPATH.'controllers/'.$this->directory.$segments[0])
)
{
//取出并删除第个元素作为directory
$this->set_directory(array_shift($segments), TRUE);
continue;
}

return $segments;
}

// This means that all segments were actually directories
return $segments;
}

// --------------------------------------------------------------------

/**
* Parse Routes
*
* Matches any routes that may exist in the config/routes.php file
* against the URI to determine if the class/method need to be remapped.
*
* 解析路由
* @return void
*/
protected function _parse_routes()
{
// Turn the segment array into a URI string
$uri = implode('/', $this->uri->segments);

// Get HTTP verb
$http_verb = isset($_SERVER['REQUEST_METHOD']) ? strtolower($_SERVER['REQUEST_METHOD']) : 'cli';

// Loop through the route array looking for wildcards
// 匹配路由自定义路由
foreach ($this->routes as $key => $val)
{// key 正则 ; val PUT、GET
// Check if route format is using HTTP verbs
if (is_array($val))
{
//转为小写
$val = array_change_key_case($val, CASE_LOWER);
if (isset($val[$http_verb]))
{
$val = $val[$http_verb];
}
else
{
continue;
}
}

// Convert wildcards to RegEx
$key = str_replace(array(':any', ':num'), array('[^/]+', '[0-9]+'), $key);

// Does the RegEx match?
// 除了字母、数字和反斜线\以外的任何字符都可以为定界符号,比如 | |、//、{}、!!等等,但是需要注意,如果没有特殊需要,我们都使用正斜线//作为正则表达式的定界符号。
if (preg_match('#^'.$key.'$#', $uri, $matches))
{
// Are we using callbacks to process back-references?
if ( ! is_string($val) && is_callable($val))
{
// Remove the original string from the matches array.
array_shift($matches);

// Execute the callback using the values in matches as its parameters.
$val = call_user_func_array($val, $matches);
}
// Are we using the default routing method for back-references?
elseif (strpos($val, '$') !== FALSE && strpos($key, '(') !== FALSE)
{
$val = preg_replace('#^'.$key.'$#', $val, $uri);
}

//还原后的请求地址
$this->_set_request(explode('/', $val));
return;
}
}

// 没有匹配到符合条件的路由
// If we got this far it means we didn't encounter a
// matching route so we'll set the site default route
$this->_set_request(array_values($this->uri->segments));
}

// --------------------------------------------------------------------

/**
* Set class name
*
* @param string $class Class name
* @return void
*/
public function set_class($class)
{
$this->class = str_replace(array('/', '.'), '', $class);
}

// --------------------------------------------------------------------

/**
* Fetch the current class
*
* @deprecated 3.0.0 Read the 'class' property instead
* @return string
*/
public function fetch_class()
{
return $this->class;
}

// --------------------------------------------------------------------

/**
* Set method name
*
* @param string $method Method name
* @return void
*/
public function set_method($method)
{
$this->method = $method;
}

// --------------------------------------------------------------------

/**
* Fetch the current method
*
* @deprecated 3.0.0 Read the 'method' property instead
* @return string
*/
public function fetch_method()
{
return $this->method;
}

// --------------------------------------------------------------------

/**
* Set directory name
*
* @param string $dir Directory name
* @param bool $append Whether we're appending rather than setting the full value
* @return void
*/
public function set_directory($dir, $append = FALSE)
{
if ($append !== TRUE OR empty($this->directory))
{
$this->directory = str_replace('.', '', trim($dir, '/')).'/';
}
else
{
$this->directory .= str_replace('.', '', trim($dir, '/')).'/';
}
}

// --------------------------------------------------------------------

/**
* Fetch directory
*
* Feches the sub-directory (if any) that contains the requested
* controller class.
*
* @deprecated 3.0.0 Read the 'directory' property instead
* @return string
*/
public function fetch_directory()
{
return $this->directory;
}

}