JavaScript——利用正则表达式实现二代身份证号码的验证

<div class="login-header"><a id="link">点击，弹出登录框</a></div>
<div class="box" id="box">
    <div class="hd" id="drop">注册信息 (可以拖拽)
        <span id="box_close">[关闭]</span>
    </div>
    <div class="bd"></div>
</div>

<style>
    .login-header { width: 100%;text-align: center;height: 30px; font-size: 24px;line-height: 30px;}
    * {margin: 0;padding: 0;}
    .box { width: 400px; height: 300px;border: 5px solid #eee;box-shadow: 2px 2px 2px 2px #666;position: absolute;top: 15%;left: 30%;display: none;}
    .hd { width: 100%; height: 25px; background-color: #7c9299; border-bottom: 1px solid #369; line-height: 25px; color: white;cursor: move;}
    #box_close {float: right; cursor: pointer;}
</style>

<script>
    // 获取“点击，弹出登录框”的链接、登录框的关闭按钮、登录框、页面背景色
    var link = document.getElementById("link");
    var closeBtn = document.getElementById("box_close");
    var login = document.getElementById("box");
    // 点击登录 显示登录框和遮罩
    link.onclick = function () { 
        login.style.display = "block";
    }
    // 点击关闭按钮 隐藏登录框和遮罩
    closeBtn.onclick = function () {
        login.style.display = "none";
    }
    // 按下键盘上的ESC键 隐藏登录框和遮罩
    document.onkeydown = function (e) {
        console.log(e.keyCode);//ESC键的键盘码是27
        if (e.keyCode === 27) {
            closeBtn.onclick();
        }
    }
</script>