https://chusonji.or.jp/common/js/vendor/form/jquery.ah-placeholder.js

1/*
2 * jQuery ah-placeholder plugin 1.0
3 *
4 * https://github.com/ahomu/jquery.ah-placeholder
5 * http://havelog.ayumusato.com/develop/javascript/e189-jquery-plugin-placeholder.html
6 *
7 * Copyright (c) 2011 Ayumu Sato ( http://havelog.ayumusato.com )
8 *
9 * Dual licensed under the MIT and GPL licenses:
10 *   http://www.opensource.org/licenses/mit-license.php
11 *   http://www.gnu.org/licenses/gpl.html
12 */
13(function($) {
14    $.fn.ahPlaceholder = function(options)
15    {
16        // property
17        var defaults = {
18                placeholderColor : 'silver',
19                necessaryColor : 'hotpink'
20            },
21            settings = $.extend({}, defaults, options);
22        // method
23        var init    = function()
24            {
25                $.data(this, 'placeholder-string', this.title);
26//                $.data(this, 'placeholder-color', this.style.color);
27                $.data(this, 'placeholder-color', $(this).css("color"));
28                var phString    = $.data(this, 'placeholder-string'),
29                    $self       = $(this);
30
31                if ( this.value === '' ) {
32                    this.value = phString;
33                }
34                if ( this.value === phString ) {
35//                    this.style.color = settings.placeholderColor;
36                      $self.css("color", $self.hasClass('necessary') ?
37                          settings.necessaryColor  :
38                          settings.placeholderColor
39                      );
40                }
41                $self.focus(onFocus);
42                $self.blur(onBlur);
43                $self.parents().filter('form').submit(onSubmit(this));
44            },
45            onFocus = function()
46            {
47                if ( this.value === $.data(this, 'placeholder-string') ) {
48                    this.value = '';
49//                    this.style.color = $.data(this, 'placeholder-color');
50                      $(this).css("color", $.data(this, 'placeholder-color'));
51                }
52            },
53            onBlur  = function()
54            {
55                if ( this.value === '' ) {
56                    this.value = $.data(this, 'placeholder-string');
57//                    this.style.color = settings.placeholderColor;
58                      $(this).css("color", $(this).hasClass('necessary') ?
59                          settings.necessaryColor  :
60                          settings.placeholderColor
61                      );
62                }
63            },
64            onSubmit= function(elm)
65            {
66                return function()
67                {
68                    if ( $(elm).val() === $.data(elm, 'placeholder-string') ) {
69                        $(elm).val('');
70                    }
71                    return true;
72                };
73            };
74        // construct
75        this.each(function()
76        {
77            init.apply(this);
78        });
79
80        return this;
81    };
82})(jQuery);