jQuery实现限制textarea文本框输入字符数量的方法

(function($) {  $.fn.extend( {    limiter: function(limit, elem) {      $(this).on("keyup focus", function() {        setCount(this, elem);      });      function setCount(src, elem) {        var chars = src.value.length;        if (chars > limit) {          src.value = src.value.substr(0, limit);          chars = limit;        }        elem.html( limit - chars );      }      setCount($(this)[0], elem);    }  });})(jQuery); //To setup the limiter, simply include a call similar to the one below:var elem = $("#chars");$("#text").limiter(100, elem);