javascript - 如何在jquery中按下按键时隐藏错误消息

Question

我有以下 HTML 和 jquery 函数来验证输入。我想在按任意键时隐藏错误消息。那么该怎么做。请帮我写按键功能。谢谢。

       function Validate() {
            var isAllValid = true;
            $('.error').hide();
            $('#error').empty();
            $('.form-group').removeClass('has-error');

            if ($('#FName').val().trim() == "") {
                $('#FName').focus();
                $('#FName').siblings('.error').show();
                $('#FName').parents('.form-group').addClass('has-error');
                isAllValid = false;
            }
            if ($('#Email').val().trim() != "" || $('#Email').val().trim() =="") {

                var expr = /^([a-zA-Z0-9_\-\.]+)@@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
                if (!expr.test($('#Email').val().trim())) {
                    $('#Email').focus();
                    $('#Email').siblings('.error').show();
                    $('#Email').parents('.form-group').addClass('has-error');
                    isAllValid = false;
                }
            }
            return isAllValid;
        }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="form-group">
            <label for="LName" class="col-sm-2 control-label">First Name</label>
            <div class="col-sm-10">
                <input type="text" class="form-control" id="LName" placeholder="Last Name">
                <span class="error">**Please provide Last Name...</span>
            </div>
        </div>

        <div class="form-group">
            <label for="Email" class="col-sm-2 control-label">Email Address</label>
            <div class="col-sm-10">

Answer 1

$(document).keypress(function(e) {
    $('.error').hide();
    });

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text">
<div class="error">please enter value</div>