js模态对话框实现

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Modal Dialog Example</title>
    <style>
        /* 模态对话框样式 */
        .modal {
            display: none;
            position: fixed;
            z-index: 1;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            overflow: auto;
            background-color: rgba(0,0,0,0.4);
        }
        .modal-content {
            background-color: #fefefe;
            margin: 15% auto;
            padding: 20px;
            border: 1px solid #888;
            width: 80%;
        }
        .close {
            color: #aaa;
            float: right;
            font-size: 28px;
            font-weight: bold;
        }
        .close:hover,
        .close:focus {
            color: black;
            text-decoration: none;
            cursor: pointer;
        }
    </style>
</head>
<body>

<button id="openModalBtn">Open Modal</button>

<!-- 模态对话框结构 -->
<div id="myModal" class="modal">
    <div class="modal-content">
        <span class="close">&times;</span>
        <p>This is a modal dialog!</p>
    </div>
</div>

<script>
    // 获取模态对话框元素
    var modal = document.getElementById("myModal");
    var btn = document.getElementById("openModalBtn");
    var span = document.getElementsByClassName("close")[0];

    // 点击按钮打开模态对话框
    btn.onclick = function() {
        modal.style.display = "block";
    }

    // 点击关闭按钮关闭模态对话框
    span.onclick = function() {
        modal.style.display = "none";
    }

    // 点击窗口外部区域关闭模态对话框
    window.onclick = function(event) {
        if (event.target == modal) {
            modal.style.display = "none";
        }
    }
</script>

</body>
</html>