1 /*
2 @author: Terry
3 @params:
4 feedback - the selector for the element that gives the user feedback. Note that this will be relative to the form the plugin is run against.
5 hardLimit - whether to stop the user being able to keep adding characters. Defaults to true.
6 useInput - whether to look for a hidden input named 'maxlength' instead of the maxlength attribute. Defaults to false.
7 words - limit by characters or words, set this to true to limit by words. Defaults to false.
8 @license:
9 @version: 1.2
10 @changes: code tidy via Ariel Flesler and fix when pasting over limit and including \t or \n
11 */
12
13 (function ($) {
14
15 $.fn.maxlength = function (settings) {
16
17 if (typeof settings == 'string') {
18 settings = { feedback : settings };
19 }
20
21 settings = $.extend({}, $.fn.maxlength.defaults, settings);
22
23 function length(el) {
24 var parts = el.value;
25 if ( settings.words )
26 parts = el.value.length ? parts.split(/\s+/) : { length : 0 };
27 return parts.length;
28 }
29
30 return this.each(function () {
31 var field = this;
32 var $field = $(field);
33 var $form = $(field.form);
34 var limit = settings.useInput ? $form.find('input[name=maxlength]').val() : $field.attr('maxlength');
35 var $charsLeft = $form.find(settings.feedback);
36
37 function limitCheck(event) {
38 var len = length(this);
39 var exceeded = len >= limit;
40 var code = event.keyCode;
41 if (!exceeded )
42 return;
43
44 switch (code) {
45 case 8: // allow delete BackSpace BackSpace
46 case 9: // Tab Tab
47 case 17: // Next
48 case 36: // Home
49 case 35: // End
50 case 37: //
51 case 38: //Up Arrow
52 case 39: //Right Arrow
53 case 40: //Dw Arrow
54 case 46: //~
55 case 65: //A
56 return;
57
58 default:
59 return settings.words && code != 32 && code != 13 && len == limit;
60 }
61 }
62
63
64 var updateCount = function () {
65 var len = length(field);
66 var diff = limit - len;
67
68 $charsLeft.html( diff || "0" );
69
70 // truncation code
71 if (settings.hardLimit && diff < 0) {
72 field.value = settings.words ?
73 // split by white space, capturing it in the result, then glue them back
74 field.value.split(/(\s+)/, (limit*2)-1).join('') :
75 field.value.substr(0, limit);
76
77 updateCount();
78 }
79 };
80 $field.keyup(updateCount).change(updateCount);
81 if (settings.hardLimit) {
82 $field.keydown(limitCheck);
83 }
84
85 updateCount();
86 });
87 };
88
89 $.fn.maxlength.defaults = {
90 useInput : false,
91 hardLimit : true,
92 feedback : '.charsLeft',
93 words : false
94 };
95
96 })(jQuery);
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