实时监测输入字符个数

//转换汉字字符的记数
 getStrLength: function (sStr) {
            var aMatch = sStr.match(/[^\x00-\x80]/g),
                strlen = (sStr.length + (!aMatch ? 0 : aMatch.length));
            return strlen;
        },

textareaL: function () {
            var ipt_imer,
                _t = this;
            $doc.on('keyup', '.proDetails textarea', function() {
                var _ipt = $(this);                         //被检测的textarea
                ipt_imer && clearTimeout(ipt_imer);
                ipt_imer = setTimeout(function() {
                    var _controls = _ipt.closest('.proDetails');
                    var _hi = _controls.find('.textWord');  //超出字符提示(80/80)
                    var _val = $.trim(_ipt.val());
                    //转换汉字字符数
                    var _valT = _t.getStrLength(_val);
                    var _num = parseInt(_hi.text().replace(/^.*\//, ''));
                    var muted = $('.muted', _hi);

                    muted.text(_valT);
                    if(_valT > _num) {
                        muted.addClass('red');
                    } else {
                        muted.removeClass('red');
                    }
                }, 50);
            });
        },