<!doctype html><html><head><meta charset="utf-8"><title>jQuery实现限制input框 ?textarea文本框输入字符数量的方法</title></head><script src="http://j2.58cdn.com.cn/js/jquery-1.8.3.js"></script><!--依赖jquery--><body>用户名:<input type="text" name="username" id="username" > ?<span style="display:none;border:0;float:right;margin-right:50px" id="t2" >用户名长度为3-6位</span> <!--我微信号 (WX-APP-PC) --><script>(function($) { ?$.fn.extend( { ???limiter: function(limit, elem) { ?????$(this).on("keyup focus", function() { ???????setCount(this, elem); ?????}); ?????function setCount(src, elem) { ???????var chars = src.value.length; ???????if (chars > limit) { ?????????src.value = src.value.substr(0, limit); ?????????chars = limit; ?????????$(‘#t2‘).show(); ???????}else{ ???????????$(‘#t2‘).hide(); ???????} ???????elem.html( limit - chars ); ?????} ?????setCount($(this)[0], elem); ???} ?});})(jQuery); ?//To setup the limiter, simply include a call similar to the one below:var elem = $("#username");$("#username").limiter(6, elem);</script></body></html>jQuery实现限制input框 ?textarea文本框输入字符数量的方法
原文地址：https://www.cnblogs.com/zc290987034/p/8618064.html