https://semillasbaratas.com/modules/correosexpress/views/js/textareaCounter.js

1/*
2 * jQuery Textarea Characters Counter Plugin v 2.0
3 * Examples and documentation at: http://roy-jin.appspot.com/jsp/textareaCounter.jsp
4 * Copyright (c) 2010 Roy Jin
5 * Version: 2.0 (11-JUN-2010)
6 * Dual licensed under the MIT and GPL licenses:
7 * http://www.opensource.org/licenses/mit-license.php
8 * http://www.gnu.org/licenses/gpl.html
9 * Requires: jQuery v1.4.2 or later
10 */
11(function($){  
12	$.fn.textareaCount = function(options, fn) {   
13		var defaults = {  
14			maxCharacterSize: -1,  
15			originalStyle: 'originalTextareaInfo',
16			warningStyle: 'warningTextareaInfo',  
17			warningNumber: 20,
18			displayFormat: '#input caracteres | #words palabras'
19		};  
20		var options = $.extend(defaults, options);
21		
22		var container = $(this);
23		
24		$("<div class='charleft'>&nbsp;</div>").insertAfter(container);
25		
26		//create charleft css
27		var charLeftCss = {
28			'width' : container.width()
29		};
30		
31		var charLeftInfo = getNextCharLeftInformation(container);
32		charLeftInfo.addClass(options.originalStyle);
33		charLeftInfo.css(charLeftCss);
34		
35		var numInput = 0;
36		var maxCharacters = options.maxCharacterSize;
37		var numLeft = 0;
38		var numWords = 0;
39				
40		container.bind('keyup', function(event){limitTextAreaByCharacterCount();})
41				 .bind('mouseover', function(event){setTimeout(function(){limitTextAreaByCharacterCount();}, 10);})
42				 .bind('paste', function(event){setTimeout(function(){limitTextAreaByCharacterCount();}, 10);});
43		
44		function limitTextAreaByCharacterCount(){
45			charLeftInfo.html(countByCharacters());
46			//function call back
47			if(typeof fn != 'undefined'){
48				fn.call(this, getInfo());
49			}
50			return true;
51		}
52		
53		function countByCharacters(){
54			var content = container.val();
55			var contentLength = content.length;
56			
57			//Start Cut
58			if(options.maxCharacterSize > 0){
59				//If copied content is already more than maxCharacterSize, chop it to maxCharacterSize.
60				if(contentLength >= options.maxCharacterSize) {
61					content = content.substring(0, options.maxCharacterSize); 				
62				}
63				
64				var newlineCount = getNewlineCount(content);
65				
66				// newlineCount new line character. For windows, it occupies 2 characters
67				var systemmaxCharacterSize = options.maxCharacterSize - newlineCount;
68				if (!isWin()){
69					 systemmaxCharacterSize = options.maxCharacterSize
70				}
71				if(contentLength > systemmaxCharacterSize){
72					//avoid scroll bar moving
73					var originalScrollTopPosition = this.scrollTop;
74					container.val(content.substring(0, systemmaxCharacterSize));
75					this.scrollTop = originalScrollTopPosition;
76				}
77				charLeftInfo.removeClass(options.warningStyle);
78				if(systemmaxCharacterSize - contentLength <= options.warningNumber){
79					charLeftInfo.addClass(options.warningStyle);
80				}
81				
82				numInput = container.val().length + newlineCount;
83				if(!isWin()){
84					numInput = container.val().length;
85				}
86			
87				numWords = countWord(getCleanedWordString(container.val()));
88				
89				numLeft = maxCharacters - numInput;
90			} else {
91				//normal count, no cut
92				var newlineCount = getNewlineCount(content);
93				numInput = container.val().length + newlineCount;
94				if(!isWin()){
95					numInput = container.val().length;
96				}
97				numWords = countWord(getCleanedWordString(container.val()));
98			}
99			
100			return formatDisplayInfo();
101		}
102		
103		function formatDisplayInfo(){
104			var format = options.displayFormat;
105			format = format.replace('#input', numInput);
106			format = format.replace('#words', numWords);
107			//When maxCharacters <= 0, #max, #left cannot be substituted.
108			if(maxCharacters > 0){
109				format = format.replace('#max', maxCharacters);
110				format = format.replace('#left', numLeft);
111			}
112			return format;
113		}
114		
115		function getInfo(){
116			var info = {
117				input: numInput,
118				max: maxCharacters,
119				left: numLeft,
120				words: numWords
121			};
122			return info;
123		}
124		
125		function getNextCharLeftInformation(container){
126				return container.next('.charleft');
127		}
128		
129		function isWin(){
130			var strOS = navigator.appVersion;
131			if (strOS.toLowerCase().indexOf('win') != -1){
132				return true;
133			}
134			return false;
135		}
136		
137		function getNewlineCount(content){
138			var newlineCount = 0;
139			for(var i=0; i<content.length;i++){
140				if(content.charAt(i) == '\n'){
141					newlineCount++;
142				}
143			}
144			return newlineCount;
145		}
146		
147		function getCleanedWordString(content){
148			var fullStr = content + " ";
149			var initial_whitespace_rExp = /^[^A-Za-z0-9]+/gi;
150			var left_trimmedStr = fullStr.replace(initial_whitespace_rExp, "");
151			var non_alphanumerics_rExp = rExp = /[^A-Za-z0-9]+/gi;
152			var cleanedStr = left_trimmedStr.replace(non_alphanumerics_rExp, " ");
153			var splitString = cleanedStr.split(" ");
154			return splitString;
155		}
156		
157		function countWord(cleanedWordString){
158			var word_count = cleanedWordString.length-1;
159			return word_count;
160		}
161	};  
162})(jQuery);