以下是一个简单的 JavaScript 弹窗代码实例。

HTML 代码：

<!-- 打开弹窗按钮 --><button id="myBtn">打开弹窗</button><!-- 弹窗 --><div id="myModal" class="modal"><!-- 弹窗内容 --><div class="modal-content"><span class="close">&times;</span><p>弹窗中的文本...</p></div></div>

CSS 代码：

/* 弹窗 (background) */.modal {display: none; /* 默认隐藏 */position: fixed; /* 固定定位 */z-index: 1; /* 设置在顶层 */left: 0;top: 0;width: 100%;height: 100%;overflow: auto;background-color: rgb(0,0,0);background-color: rgba(0,0,0,0.4);}/* 弹窗内容 */.modal-content {background-color: #fefefe;margin: 15% auto;padding: 20px;border: 1px solid #888;width: 80%;}/* 关闭按钮 */.close {color: #aaa;float: right;font-size: 28px;font-weight: bold;}.close:hover,.close:focus {color: black;text-decoration: none;cursor: pointer;}

JavaScript 代码：

// 获取弹窗var modal = document.getElementById('myModal');// 打开弹窗的按钮对象var btn = document.getElementById("myBtn");// 获取 <span> 元素 用于关闭弹窗var span = document.querySelector('.close');// 点击按钮打开弹窗btn.onclick = function() {modal.style.display = "block";}// 点击 <span> (x), 关闭弹窗span.onclick = function() {modal.style.display = "none";}// 在用户点击其他地方时 关闭弹窗window.onclick = function(event) {if (event.target == modal) {modal.style.display = "none";}}

在线演示

弹窗添加头部和底部

HTML 代码：

<!-- 打开弹窗按钮 --><button id="myBtn">打开弹窗</button><!-- 弹窗 --><div id="myModal" class="modal"><!-- 弹窗内容 --><div class="modal-content"><div class="modal-header"><span class="close">&times;</span><h2>弹窗头部</h2></div><div class="modal-body"><p>弹窗文本...</p><p>弹窗文本...</p></div><div class="modal-footer"><h3>弹窗底部</h3></div></div></div>

CSS 代码：

/* 弹窗 (background) */.modal {display: none; /* 默认隐藏 */position: fixed;z-index: 1;padding-top: 100px;left: 0;top: 0;width: 100%;height: 100%;overflow: auto;background-color: rgb(0,0,0);background-color: rgba(0,0,0,0.4);}/* 弹窗内容 */.modal-content {position: relative;background-color: #fefefe;margin: auto;padding: 0;border: 1px solid #888;width: 80%;box-shadow: 0 4px 8px 0 rgba(0,0,0,0.2),0 6px 20px 0 rgba(0,0,0,0.19);-webkit-animation-name: animatetop;-webkit-animation-duration: 0.4s;animation-name: animatetop;animation-duration: 0.4s}/* 添加动画 */@-webkit-keyframes animatetop {from {top:-300px; opacity:0}to {top:0; opacity:1}}@keyframes animatetop {from {top:-300px; opacity:0}to {top:0; opacity:1}}/* 关闭按钮 */.close {color: white;float: right;font-size: 28px;font-weight: bold;}.close:hover,.close:focus {color: #000;text-decoration: none;cursor: pointer;}.modal-header {padding: 2px 16px;background-color: #5cb85c;color: white;}.modal-body {padding: 2px 16px;}.modal-footer {padding: 2px 16px;background-color: #5cb85c;color: white;}

在线演示

在底部显示的弹窗