切片

export function section(): void {
    const ul = document.getElementById('ul');
    const total = 10001;
    const once = 20;
    function loop(curTotal: number): void {
        if (curTotal <= 0) {
            return;
        }
        const pageCount = Math.min(curTotal, once);
        window.requestAnimationFrame(() => {
            const fragment = document.createDocumentFragment();
            for (let i = 0; i < pageCount; i++) {
                const li = document.createElement('li');
                li.innerText = `${i}`;
                fragment.appendChild(li);
            }
            ul && ul.appendChild(fragment);
        });
        loop(curTotal - pageCount);
    }
    loop(total);
}