如何在输入占位符中创建输入轮播？

要在输入占位符中创建输入轮播，您可以使用HTML、CSS和JavaScript的组合来实现。以下是一个简单的示例，展示了如何创建一个具有轮播功能的输入占位符。

HTML

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Input Carousel Placeholder</title>
    <link rel="stylesheet" href="styles.css">
</head>
<body>
    <div class="input-container">
        <input type="text" id="inputField" placeholder=" ">
        <div class="placeholder-carousel">
            <span>First placeholder</span>
            <span>Second placeholder</span>
            <span>Third placeholder</span>
        </div>
    </div>
    <script src="script.js"></script>
</body>
</html>

CSS (styles.css)

.input-container {
    position: relative;
    width: 300px;
}

input {
    width: 100%;
    padding: 10px;
    font-size: 16px;
}

.placeholder-carousel {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    pointer-events: none;
    color: #999;
    font-size: 16px;
}

JavaScript (script.js)

const inputField = document.getElementById('inputField');
const placeholders = document.querySelectorAll('.placeholder-carousel span');
let currentIndex = 0;

function updatePlaceholder() {
    inputField.placeholder = placeholders[currentIndex].textContent;
    currentIndex = (currentIndex + 1) % placeholders.length;
}

inputField.addEventListener('focus', () => {
    clearInterval(intervalId);
});

inputField.addEventListener('blur', () => {
    intervalId = setInterval(updatePlaceholder, 2000);
});

let intervalId = setInterval(updatePlaceholder, 2000);

解释

HTML: 创建一个输入框和一个包含多个占位符文本的容器。
CSS: 设置输入框和占位符容器的样式，确保占位符容器在输入框上方且不干扰输入。
JavaScript: 使用setInterval定时更新输入框的占位符文本，实现轮播效果。当输入框获得焦点时，停止轮播；当输入框失去焦点时，重新开始轮播。