summaryrefslogtreecommitdiffstats
path: root/user_guide_src/source/libraries/form_validation.rst
blob: 3e8855f60a441fdd77facb05ea93d38d3480b074 (plain)
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
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
###############
Form Validation
###############

CodeIgniter provides a comprehensive form validation and data prepping
class that helps minimize the amount of code you'll write.

.. contents:: Page Contents

********
Overview
********

Before explaining CodeIgniter's approach to data validation, let's
describe the ideal scenario:

#. A form is displayed.
#. You fill it in and submit it.
#. If you submitted something invalid, or perhaps missed a required
   item, the form is redisplayed containing your data along with an
   error message describing the problem.
#. This process continues until you have submitted a valid form.

On the receiving end, the script must:

#. Check for required data.
#. Verify that the data is of the correct type, and meets the correct
   criteria. For example, if a username is submitted it must be
   validated to contain only permitted characters. It must be of a
   minimum length, and not exceed a maximum length. The username can't
   be someone else's existing username, or perhaps even a reserved word.
   Etc.
#. Sanitize the data for security.
#. Pre-format the data if needed (Does the data need to be trimmed? HTML
   encoded? Etc.)
#. Prep the data for insertion in the database.

Although there is nothing terribly complex about the above process, it
usually requires a significant amount of code, and to display error
messages, various control structures are usually placed within the form
HTML. Form validation, while simple to create, is generally very messy
and tedious to implement.

************************
Form Validation Tutorial
************************

What follows is a "hands on" tutorial for implementing CodeIgniters Form
Validation.

In order to implement form validation you'll need three things:

#. A :doc:`View <../general/views>` file containing a form.
#. A View file containing a "success" message to be displayed upon
   successful submission.
#. A :doc:`controller <../general/controllers>` function to receive and
   process the submitted data.

Let's create those three things, using a member sign-up form as the
example.

The Form
========

Using a text editor, create a form called myform.php. In it, place this
code and save it to your applications/views/ folder::

	<html>
	<head>
	<title>My Form</title>
	</head>
	<body>

	<?php echo validation_errors(); ?>

	<?php echo form_open('form'); ?>

	<h5>Username</h5>
	<input type="text" name="username" value="" size="50" />

	<h5>Password</h5>
	<input type="text" name="password" value="" size="50" />

	<h5>Password Confirm</h5>
	<input type="text" name="passconf" value="" size="50" />

	<h5>Email Address</h5>
	<input type="text" name="email" value="" size="50" />

	<div><input type="submit" value="Submit" /></div>

	</form>

	</body>
	</html>

The Success Page
================

Using a text editor, create a form called formsuccess.php. In it, place
this code and save it to your applications/views/ folder::

	<html>
	<head>
	<title>My Form</title>
	</head>
	<body>

	<h3>Your form was successfully submitted!</h3>

	<p><?php echo anchor('form', 'Try it again!'); ?></p>

	</body>
	</html>

The Controller
==============

Using a text editor, create a controller called form.php. In it, place
this code and save it to your applications/controllers/ folder::

	<?php

	class Form extends CI_Controller {

		public function index()
		{
			$this->load->helper(array('form', 'url'));

			$this->load->library('form_validation');

			if ($this->form_validation->run() == FALSE)
			{
				$this->load->view('myform');
			}
			else
			{
				$this->load->view('formsuccess');
			}
		}
	}
	?>

Try it!
=======

To try your form, visit your site using a URL similar to this one::

	example.com/index.php/form/

If you submit the form you should simply see the form reload. That's
because you haven't set up any validation rules yet.

**Since you haven't told the Form Validation class to validate anything
yet, it returns FALSE (boolean false) by default. The run() function
only returns TRUE if it has successfully applied your rules without any
of them failing.**

Explanation
===========

You'll notice several things about the above pages:

The form (myform.php) is a standard web form with a couple exceptions:

#. It uses a form helper to create the form opening. Technically, this
   isn't necessary. You could create the form using standard HTML.
   However, the benefit of using the helper is that it generates the
   action URL for you, based on the URL in your config file. This makes
   your application more portable in the event your URLs change.
#. At the top of the form you'll notice the following function call:
   ::

	<?php echo validation_errors(); ?>

   This function will return any error messages sent back by the
   validator. If there are no messages it returns an empty string.

The controller (form.php) has one function: index(). This function
initializes the validation class and loads the form helper and URL
helper used by your view files. It also runs the validation routine.
Based on whether the validation was successful it either presents the
form or the success page.

.. _setting-validation-rules:

Setting Validation Rules
========================

CodeIgniter lets you set as many validation rules as you need for a
given field, cascading them in order, and it even lets you prep and
pre-process the field data at the same time. To set validation rules you
will use the set_rules() function::

	$this->form_validation->set_rules();

The above function takes **three** parameters as input:

#. The field name - the exact name you've given the form field.
#. A "human" name for this field, which will be inserted into the error
   message. For example, if your field is named "user" you might give it
   a human name of "Username".
#. The validation rules for this form field.

.. note:: If you would like the field
	name to be stored in a language file, please see :ref:`translating-field-names`.

Here is an example. In your controller (form.php), add this code just
below the validation initialization function::

	$this->form_validation->set_rules('username', 'Username', 'required');
	$this->form_validation->set_rules('password', 'Password', 'required');
	$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');
	$this->form_validation->set_rules('email', 'Email', 'required');

Your controller should now look like this::

	<?php

	class Form extends CI_Controller {

		public function index()
		{
			$this->load->helper(array('form', 'url'));

			$this->load->library('form_validation');

			$this->form_validation->set_rules('username', 'Username', 'required');
			$this->form_validation->set_rules('password', 'Password', 'required');
			$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');
			$this->form_validation->set_rules('email', 'Email', 'required');

			if ($this->form_validation->run() == FALSE)
			{
				$this->load->view('myform');
			}
			else
			{
				$this->load->view('formsuccess');
			}
		}
	}
	?>

Now submit the form with the fields blank and you should see the error
messages. If you submit the form with all the fields populated you'll
see your success page.

.. note:: The form fields are not yet being re-populated with the data
	when there is an error. We'll get to that shortly.

Setting Rules Using an Array
============================

Before moving on it should be noted that the rule setting function can
be passed an array if you prefer to set all your rules in one action. If
you use this approach you must name your array keys as indicated::

	$config = array(
	               array(
	                     'field'   => 'username', 
	                     'label'   => 'Username', 
	                     'rules'   => 'required'
	                  ),
	               array(
	                     'field'   => 'password', 
	                     'label'   => 'Password', 
	                     'rules'   => 'required'
	                  ),
	               array(
	                     'field'   => 'passconf', 
	                     'label'   => 'Password Confirmation', 
	                     'rules'   => 'required'
	                  ),   
	               array(
	                     'field'   => 'email', 
	                     'label'   => 'Email', 
	                     'rules'   => 'required'
	                  )
	            );

	$this->form_validation->set_rules($config);

Cascading Rules
===============

CodeIgniter lets you pipe multiple rules together. Let's try it. Change
your rules in the third parameter of rule setting function, like this::

	$this->form_validation->set_rules('username', 'Username', 'required|min_length[5]|max_length[12]|is_unique[users.username]');
	$this->form_validation->set_rules('password', 'Password', 'required|matches[passconf]');
	$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');
	$this->form_validation->set_rules('email', 'Email', 'required|valid_email|is_unique[users.email]');
	

The above code sets the following rules:

#. The username field be no shorter than 5 characters and no longer than
   12.
#. The password field must match the password confirmation field.
#. The email field must contain a valid email address.

Give it a try! Submit your form without the proper data and you'll see
new error messages that correspond to your new rules. There are numerous
rules available which you can read about in the validation reference.

Prepping Data
=============

In addition to the validation functions like the ones we used above, you
can also prep your data in various ways. For example, you can set up
rules like this::

	$this->form_validation->set_rules('username', 'Username', 'trim|required|min_length[5]|max_length[12]|xss_clean');
	$this->form_validation->set_rules('password', 'Password', 'trim|required|matches[passconf]|md5');
	$this->form_validation->set_rules('passconf', 'Password Confirmation', 'trim|required');
	$this->form_validation->set_rules('email', 'Email', 'trim|required|valid_email');

In the above example, we are "trimming" the fields, converting the
password to MD5, and running the username through the "xss_clean"
function, which removes malicious data.

**Any native PHP function that accepts one parameter can be used as a
rule, like htmlspecialchars, trim, MD5, etc.**

.. note:: You will generally want to use the prepping functions
	**after** the validation rules so if there is an error, the original
	data will be shown in the form.

Re-populating the form
======================

Thus far we have only been dealing with errors. It's time to repopulate
the form field with the submitted data. CodeIgniter offers several
helper functions that permit you to do this. The one you will use most
commonly is::

	set_value('field name')

Open your myform.php view file and update the **value** in each field
using the set_value() function:

**Don't forget to include each field name in the set_value()
functions!**

::

	<html>
	<head>
	<title>My Form</title>
	</head>
	<body>

	<?php echo validation_errors(); ?>

	<?php echo form_open('form'); ?>

	<h5>Username</h5>
	<input type="text" name="username" value="<?php echo set_value('username'); ?>" size="50" />

	<h5>Password</h5>
	<input type="text" name="password" value="<?php echo set_value('password'); ?>" size="50" />

	<h5>Password Confirm</h5>
	<input type="text" name="passconf" value="<?php echo set_value('passconf'); ?>" size="50" />

	<h5>Email Address</h5>
	<input type="text" name="email" value="<?php echo set_value('email'); ?>" size="50" />

	<div><input type="submit" value="Submit" /></div>

	</form>

	</body>
	</html>

Now reload your page and submit the form so that it triggers an error.
Your form fields should now be re-populated

.. note:: The :ref:`function-reference` section below
	contains functions that permit you to re-populate <select> menus, radio
	buttons, and checkboxes.

**Important Note:** If you use an array as the name of a form field, you
must supply it as an array to the function. Example::

	<input type="text" name="colors[]" value="<?php echo set_value('colors[]'); ?>" size="50" />

For more info please see the :ref:`using-arrays-as-field-names` section below.

Callbacks: Your own Validation Functions
========================================

The validation system supports callbacks to your own validation
functions. This permits you to extend the validation class to meet your
needs. For example, if you need to run a database query to see if the
user is choosing a unique username, you can create a callback function
that does that. Let's create a example of this.

In your controller, change the "username" rule to this::

	$this->form_validation->set_rules('username', 'Username', 'callback_username_check');

Then add a new function called username_check to your controller.
Here's how your controller should now look::

	<?php

	class Form extends CI_Controller {

		public function index()
		{
			$this->load->helper(array('form', 'url'));

			$this->load->library('form_validation');

			$this->form_validation->set_rules('username', 'Username', 'callback_username_check');
			$this->form_validation->set_rules('password', 'Password', 'required');
			$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');
			$this->form_validation->set_rules('email', 'Email', 'required|is_unique[users.email]');

			if ($this->form_validation->run() == FALSE)
			{
				$this->load->view('myform');
			}
			else
			{
				$this->load->view('formsuccess');
			}
		}

		public function username_check($str)
		{
			if ($str == 'test')
			{
				$this->form_validation->set_message('username_check', 'The %s field can not be the word "test"');
				return FALSE;
			}
			else
			{
				return TRUE;
			}
		}

	}
	?>

Reload your form and submit it with the word "test" as the username. You
can see that the form field data was passed to your callback function
for you to process.

To invoke a callback just put the function name in a rule, with
"callback\_" as the rule **prefix**. If you need to receive an extra
parameter in your callback function, just add it normally after the
function name between square brackets, as in: "callback_foo**[bar]**",
then it will be passed as the second argument of your callback function.

.. note:: You can also process the form data that is passed to your
	callback and return it. If your callback returns anything other than a
	boolean TRUE/FALSE it is assumed that the data is your newly processed
	form data.

.. _setting-error-messages:

Setting Error Messages
======================

All of the native error messages are located in the following language
file: language/english/form_validation_lang.php

To set your own custom message you can either edit that file, or use the
following function::

	$this->form_validation->set_message('rule', 'Error Message');

Where rule corresponds to the name of a particular rule, and Error
Message is the text you would like displayed.

If you include %s in your error string, it will be replaced with the
"human" name you used for your field when you set your rules.

In the "callback" example above, the error message was set by passing
the name of the function::

	$this->form_validation->set_message('username_check')

You can also override any error message found in the language file. For
example, to change the message for the "required" rule you will do this::

	$this->form_validation->set_message('required', 'Your custom message here');

.. _translating-field-names:

Translating Field Names
=======================

If you would like to store the "human" name you passed to the
set_rules() function in a language file, and therefore make the name
able to be translated, here's how:

First, prefix your "human" name with lang:, as in this example::

	 $this->form_validation->set_rules('first_name', 'lang:first_name', 'required');

Then, store the name in one of your language file arrays (without the
prefix)::

	$lang['first_name'] = 'First Name';

.. note:: If you store your array item in a language file that is not
	loaded automatically by CI, you'll need to remember to load it in your
	controller using::

	$this->lang->load('file_name');

See the :doc:`Language Class <language>` page for more info regarding
language files.

.. _changing-delimiters:

Changing the Error Delimiters
=============================

By default, the Form Validation class adds a paragraph tag (<p>) around
each error message shown. You can either change these delimiters
globally, individually, or change the defaults in a config file.

#. **Changing delimiters Globally**
   To globally change the error delimiters, in your controller function,
   just after loading the Form Validation class, add this::

      $this->form_validation->set_error_delimiters('<div class="error">', '</div>');

   In this example, we've switched to using div tags.

#. **Changing delimiters Individually**
   Each of the two error generating functions shown in this tutorial can
   be supplied their own delimiters as follows::

      <?php echo form_error('field name', '<div class="error">', '</div>'); ?>

   Or::

      <?php echo validation_errors('<div class="error">', '</div>'); ?>

#. **Set delimiters in a config file**
   You can add your error delimiters in application/config/form_validation.php as follows::
   
      $config['error_prefix'] = '<div class="error_prefix">';
      $config['error_suffix'] = '</div>';


Showing Errors Individually
===========================

If you prefer to show an error message next to each form field, rather
than as a list, you can use the form_error() function.

Try it! Change your form so that it looks like this::

	<h5>Username</h5>
	<?php echo form_error('username'); ?>
	<input type="text" name="username" value="<?php echo set_value('username'); ?>" size="50" />

	<h5>Password</h5>
	<?php echo form_error('password'); ?>
	<input type="text" name="password" value="<?php echo set_value('password'); ?>" size="50" />

	<h5>Password Confirm</h5>
	<?php echo form_error('passconf'); ?>
	<input type="text" name="passconf" value="<?php echo set_value('passconf'); ?>" size="50" />

	<h5>Email Address</h5>
	<?php echo form_error('email'); ?>
	<input type="text" name="email" value="<?php echo set_value('email'); ?>" size="50" />

If there are no errors, nothing will be shown. If there is an error, the
message will appear.

**Important Note:** If you use an array as the name of a form field, you
must supply it as an array to the function. Example::

	<?php echo form_error('options[size]'); ?>
	<input type="text" name="options[size]" value="<?php echo set_value("options[size]"); ?>" size="50" />

For more info please see the :ref:`using-arrays-as-field-names` section below.

Validating an Array (other than $_POST)
=======================================

Sometimes you may want to validate an array that does not originate from $_POST data.

In this case, you can specify the array to be validated::
	
	$data = array(
			'username' => 'johndoe',
			'password' => 'mypassword',
		 	'passconf' => 'mypassword'
		);

	$this->form_validation->set_data($data);

Creating validation rules, running the validation and retrieving error messages works the same whether you are
validating $_POST data or an array.

**Important Note:** If you want to validate more than one array during a single execution, then you should	
call the reset_validation() function before setting up rules and validating the new array.

For more info please see the :ref:`function-reference` section below.

-.. _saving-groups:

************************************************
Saving Sets of Validation Rules to a Config File
************************************************

A nice feature of the Form Validation class is that it permits you to
store all your validation rules for your entire application in a config
file. You can organize these rules into "groups". These groups can
either be loaded automatically when a matching controller/function is
called, or you can manually call each set as needed.

How to save your rules
======================

To store your validation rules, simply create a file named
form_validation.php in your application/config/ folder. In that file
you will place an array named $config with your rules. As shown earlier,
the validation array will have this prototype::

	$config = array(
	               array(
	                     'field'   => 'username', 
	                     'label'   => 'Username', 
	                     'rules'   => 'required'
	                  ),
	               array(
	                     'field'   => 'password', 
	                     'label'   => 'Password', 
	                     'rules'   => 'required'
	                  ),
	               array(
	                     'field'   => 'passconf', 
	                     'label'   => 'Password Confirmation', 
	                     'rules'   => 'required'
	                  ),   
	               array(
	                     'field'   => 'email', 
	                     'label'   => 'Email', 
	                     'rules'   => 'required'
	                  )
	            );

Your validation rule file will be loaded automatically and used when you
call the run() function.

Please note that you MUST name your array $config.

Creating Sets of Rules
======================

In order to organize your rules into "sets" requires that you place them
into "sub arrays". Consider the following example, showing two sets of
rules. We've arbitrarily called these two rules "signup" and "email".
You can name your rules anything you want::

	$config = array(
	                 'signup' => array(
	                                    array(
	                                            'field' => 'username',
	                                            'label' => 'Username',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'password',
	                                            'label' => 'Password',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'passconf',
	                                            'label' => 'PasswordConfirmation',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'email',
	                                            'label' => 'Email',
	                                            'rules' => 'required'
	                                         )
	                                    ),
	                 'email' => array(
	                                    array(
	                                            'field' => 'emailaddress',
	                                            'label' => 'EmailAddress',
	                                            'rules' => 'required|valid_email'
	                                         ),
	                                    array(
	                                            'field' => 'name',
	                                            'label' => 'Name',
	                                            'rules' => 'required|alpha'
	                                         ),
	                                    array(
	                                            'field' => 'title',
	                                            'label' => 'Title',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'message',
	                                            'label' => 'MessageBody',
	                                            'rules' => 'required'
	                                         )
	                                    )                          
	               );

Calling a Specific Rule Group
=============================

In order to call a specific group you will pass its name to the run()
function. For example, to call the signup rule you will do this::

	if ($this->form_validation->run('signup') == FALSE)
	{
	   $this->load->view('myform');
	}
	else
	{
	   $this->load->view('formsuccess');
	}

Associating a Controller Function with a Rule Group
===================================================

An alternate (and more automatic) method of calling a rule group is to
name it according to the controller class/function you intend to use it
with. For example, let's say you have a controller named Member and a
function named signup. Here's what your class might look like::

	<?php

	class Member extends CI_Controller {

	   function signup()
	   {      
	      $this->load->library('form_validation');

	      if ($this->form_validation->run() == FALSE)
	      {
	         $this->load->view('myform');
	      }
	      else
	      {
	         $this->load->view('formsuccess');
	      }
	   }
	}
	?>

In your validation config file, you will name your rule group
member/signup::

	$config = array(
	           'member/signup' => array(
	                                    array(
	                                            'field' => 'username',
	                                            'label' => 'Username',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'password',
	                                            'label' => 'Password',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'passconf',
	                                            'label' => 'PasswordConfirmation',
	                                            'rules' => 'required'
	                                         ),
	                                    array(
	                                            'field' => 'email',
	                                            'label' => 'Email',
	                                            'rules' => 'required'
	                                         )
	                                    )
	               );

When a rule group is named identically to a controller class/function it
will be used automatically when the run() function is invoked from that
class/function.

.. _using-arrays-as-field-names:

***************************
Using Arrays as Field Names
***************************

The Form Validation class supports the use of arrays as field names.
Consider this example::

	<input type="text" name="options[]" value="" size="50" />

If you do use an array as a field name, you must use the EXACT array
name in the :ref:`Helper Functions <helper-functions>` that require the
field name, and as your Validation Rule field name.

For example, to set a rule for the above field you would use::

	$this->form_validation->set_rules('options[]', 'Options', 'required');

Or, to show an error for the above field you would use::

	<?php echo form_error('options[]'); ?>

Or to re-populate the field you would use::

	<input type="text" name="options[]" value="<?php echo set_value('options[]'); ?>" size="50" />

You can use multidimensional arrays as field names as well. For example::

	<input type="text" name="options[size]" value="" size="50" />

Or even::

	<input type="text" name="sports[nba][basketball]" value="" size="50" />

As with our first example, you must use the exact array name in the
helper functions::

	<?php echo form_error('sports[nba][basketball]'); ?>

If you are using checkboxes (or other fields) that have multiple
options, don't forget to leave an empty bracket after each option, so
that all selections will be added to the POST array::

	<input type="checkbox" name="options[]" value="red" />
	<input type="checkbox" name="options[]" value="blue" />
	<input type="checkbox" name="options[]" value="green" />

Or if you use a multidimensional array::

	<input type="checkbox" name="options[color][]" value="red" />
	<input type="checkbox" name="options[color][]" value="blue" />
	<input type="checkbox" name="options[color][]" value="green" />

When you use a helper function you'll include the bracket as well::

	<?php echo form_error('options[color][]'); ?>


**************
Rule Reference
**************

The following is a list of all the native rules that are available to
use:

========================= ========== ============================================================================================= =======================
Rule                      Parameter  Description                                                                                   Example
========================= ========== ============================================================================================= =======================
**required**              No         Returns FALSE if the form element is empty.                                                                          
**matches**               Yes        Returns FALSE if the form element does not match the one in the parameter.                    matches[form_item]     
**is_unique**             Yes        Returns FALSE if the form element is not unique to the                                        is_unique[table.field] 
                                     table and field name in the parameter. is_unique[table.field]                                                        
**max_length**            Yes        Returns FALSE if the form element is longer then the parameter value.                         max_length[12]         
**exact_length**          Yes        Returns FALSE if the form element is not exactly the parameter value.                         exact_length[8]        
**greater_than**          Yes        Returns FALSE if the form element is less than or equal to the parameter value or not         greater_than[8]
                                     numeric.
**greater_than_equal_to** Yes        Returns FALSE if the form element is less than the parameter value,                           greater_than_equal_to[8]
                                     or not numeric.
**less_than**             Yes        Returns FALSE if the form element is greater than or equal to the parameter value or          less_than[8]
                                     not numeric.
**less_than_equal_to**    Yes        Returns FALSE if the form element is greater than the parameter value,                        less_than_equal_to[8]
                                     or not numeric.
**alpha**                 No         Returns FALSE if the form element contains anything other than alphabetical characters.                              
**alpha_numeric**         No         Returns FALSE if the form element contains anything other than alpha-numeric characters.                             
**alpha_dash**            No         Returns FALSE if the form element contains anything other than alpha-numeric characters,                             
                                     underscores or dashes.                                                                                               
**numeric**               No         Returns FALSE if the form element contains anything other than numeric characters.                                   
**integer**               No         Returns FALSE if the form element contains anything other than an integer.                                           
**decimal**               No         Returns FALSE if the form element contains anything other than a decimal number.                                     
**is_natural**            No         Returns FALSE if the form element contains anything other than a natural number:
                                     0, 1, 2, 3, etc.
**is_natural_no_zero**    No         Returns FALSE if the form element contains anything other than a natural
                                     number, but not zero: 1, 2, 3, etc.
**is_unique**             Yes        Returns FALSE if the form element is not unique in a database table.                          is_unique[table.field] 
**valid_email**           No         Returns FALSE if the form element does not contain a valid email address.
**valid_emails**          No         Returns FALSE if any value provided in a comma separated list is not a valid email.
**valid_ip**              No         Returns FALSE if the supplied IP is not valid.
**valid_base64**          No         Returns FALSE if the supplied string contains anything other than valid Base64 characters.
========================= ========== ============================================================================================= =======================

.. note:: These rules can also be called as discrete functions. For
	example::

		$this->form_validation->required($string);

.. note:: You can also use any native PHP functions that permit one
	parameter.

******************
Prepping Reference
******************

The following is a list of all the prepping functions that are available
to use:

==================== ========= ===================================================================================================
Name                 Parameter Description
==================== ========= ===================================================================================================
**xss_clean**        No        Runs the data through the XSS filtering function, described in the :doc:`Input Class <input>` page.
**prep_for_form**    No        Converts special characters so that HTML data can be shown in a form field without breaking it.
**prep_url**         No        Adds "\http://" to URLs if missing.
**strip_image_tags** No        Strips the HTML from image tags leaving the raw URL.
**encode_php_tags**  No        Converts PHP tags to entities.
==================== ========= ===================================================================================================

.. note:: You can also use any native PHP functions that permit one
	parameter, like trim, htmlspecialchars, urldecode, etc.

.. _function-reference:

******************
Function Reference
******************

.. php:class:: Form_validation

The following functions are intended for use in your controller
functions.

$this->form_validation->set_rules();
======================================

	.. php:method:: set_rules ($field, $label = '', $rules = '')

		:param string $field: The field name
		:param string $label: The field label
		:param string $rules: The rules, seperated by a pipe "|"
		:rtype: Object
	
		Permits you to set validation rules, as described in the tutorial
		sections above:

	-  :ref:`setting-validation-rules`
	-  :ref:`saving-groups`

$this->form_validation->run();
===============================
	
	.. php:method:: run ($group = '')

		:param string $group: The name of the validation group to run
		:rtype: Boolean
	
		Runs the validation routines. Returns boolean TRUE on success and FALSE
		on failure. You can optionally pass the name of the validation group via
		the function, as described in: :ref:`saving-groups`

$this->form_validation->set_message();
========================================
	
	.. php:method:: set_message ($lang, $val = '')

		:param string $lang: The rule the message is for
		:param string $val: The message
		:rtype: Object

		Permits you to set custom error messages. See :ref:`setting-error-messages`

$this->form_validation->set_data();
========================================
	
	.. php:method:: set_data ($data = '')

		:param array $data: The data to validate

		Permits you to set an array for validation, instead of using the default
		$_POST array.

$this->form_validation->reset_validation();
========================================

 .. php:method:: reset_validation ()

    Permits you to reset the validation when you validate more than one array.
	This function should be called before validating each new array.

$this->form_validation->error_array();
========================================
	
	.. php:method:: error_array ()

		:rtype: Array

		Returns the error messages as an array.

.. _helper-functions:

****************
Helper Reference
****************

The following helper functions are available for use in the view files
containing your forms. Note that these are procedural functions, so they
**do not** require you to prepend them with $this->form_validation.

form_error()
=============

Shows an individual error message associated with the field name
supplied to the function. Example::

	<?php echo form_error('username'); ?>

The error delimiters can be optionally specified. See the
:ref:`changing-delimiters` section above.

validation_errors()
====================

Shows all error messages as a string: Example::

	<?php echo validation_errors(); ?>

The error delimiters can be optionally specified. See the 
:ref:`changing-delimiters` section above.

set_value()
============

Permits you to set the value of an input form or textarea. You must
supply the field name via the first parameter of the function. The
second (optional) parameter allows you to set a default value for the
form. Example::

	<input type="text" name="quantity" value="<?php echo set_value('quantity', '0'); ?>" size="50" />

The above form will show "0" when loaded for the first time.

set_select()
=============

If you use a <select> menu, this function permits you to display the
menu item that was selected. The first parameter must contain the name
of the select menu, the second parameter must contain the value of each
item, and the third (optional) parameter lets you set an item as the
default (use boolean TRUE/FALSE).

Example::

	<select name="myselect">
	<option value="one" <?php echo set_select('myselect', 'one', TRUE); ?> >One</option>
	<option value="two" <?php echo set_select('myselect', 'two'); ?> >Two</option>
	<option value="three" <?php echo set_select('myselect', 'three'); ?> >Three</option>
	</select>

set_checkbox()
===============

Permits you to display a checkbox in the state it was submitted. The
first parameter must contain the name of the checkbox, the second
parameter must contain its value, and the third (optional) parameter
lets you set an item as the default (use boolean TRUE/FALSE). Example::

	<input type="checkbox" name="mycheck[]" value="1" <?php echo set_checkbox('mycheck[]', '1'); ?> />
	<input type="checkbox" name="mycheck[]" value="2" <?php echo set_checkbox('mycheck[]', '2'); ?> />

set_radio()
============

Permits you to display radio buttons in the state they were submitted.
This function is identical to the **set_checkbox()** function above.

::

	<input type="radio" name="myradio" value="1" <?php echo  set_radio('myradio', '1', TRUE); ?> />
	<input type="radio" name="myradio" value="2" <?php echo  set_radio('myradio', '2'); ?> />