js控制滑动窗口

function throttle(func, wait) {
    let timeout = null;
    return function() {
        if (!timeout) {
            timeout = setTimeout(() => {
                func.apply(this, arguments);
                timeout = null;
            }, wait);
        }
    };
}

window.addEventListener('scroll', throttle(function() {
    // 处理滚动事件
}, 200));

function smoothScrollTo(targetY, duration) {
    const startY = window.scrollY;
    const distance = targetY - startY;
    const startTime = performance.now();

    function animate(currentTime) {
        const elapsed = currentTime - startTime;
        const progress = Math.min(elapsed / duration, 1);
        window.scrollTo(0, startY + distance * easeInOutQuad(progress));
        if (progress < 1) {
            requestAnimationFrame(animate);
        }
    }

    function easeInOutQuad(t) {
        return t < 0.5 ? 2 * t * t : -1 + (4 - 2 * t) * t;
    }

    requestAnimationFrame(animate);
}

// 使用示例：平滑滚动到页面顶部
document.getElementById('back-to-top').addEventListener('click', function() {
    smoothScrollTo(0, 600);
});