The function of real-time counting of words in JavaScript input box
This article mainly introduces the real-time statistical update of the number of words in the input box JavaScript, which has a certain reference value. Interested friends can refer to it
In front-end development, many In this case, the input content needs to be verified. The real-time statistics function, for fixed-length input, allows users to clarify input boundaries in real time and arrange content reasonably.
Real-time statistical update of word count
The following will take [Message Content] as an example to design and implement the real-time statistical update function of word count in the input box.
The project structure is as follows:
message
message.css
message.js
message.tpl
1. Define web page elements in the message.tpl file
//移动端微信公众号开发 <p class="weui-cellbd"> <textarea id="content" class="weui-textarea" placeholder="新消息内容" rows="3"> </textarea> <p class="weui-textarea-counter"> <span class="contentcount">0</span>/200 </p> </p> //web端业务开发 <p class="modal-body" style="box-sizing: border-box;"> <form id="newtaskform" class="form-horizontal"></form> </p>
2. Bind events in the message.js file for statisticsInput characters
//移动端 tooltips提示形式 $('#content').bind('input propertychange', function () { var fizeNum = $(this).val().length; if (fizeNum > 200) { var char = $(this).val(); char = char.substr(0, 200); $(this).val(char); fizeNum = 200; tooltipsShow('消息内容不能超过200字'); } $(this).parent().find('.contentcount').text(fizeNum); }); //web网页span提示形式 FileName = '<p class="form-group" id="text"><label class="col-sm-3 control-label" id="textlabel"><span class="dot"></span>消息内容</label>'+ '<p class="col-sm-9 input-container "><textarea id="msgcontent" name="text" rows="8" style="width:100%;padding-right:20px"></textarea>' + '<p class="counter" style="float:right;">' + '<span id="texttips" style="display: none; color: #ff0000;">消息内容超出最大限制</span><span class="contentcount">0</span>/200</p>' + '</p></p>'; $("#newtaskform").append(FileName); $('#msgcontent').bind('input propertychange', function () { var fizeNum = $(this).val().length; if (fizeNum > 200) { var char = $(this).val(); char = char.substr(0, 200); $(this).val(char); fizeNum = 200; $("#texttips").show(); }else{ $("#texttips").hide(); } $(this).parent().find('.contentcount').text(fizeNum); });
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