js获取document高度

var documentHeight = document.documentElement.scrollHeight;
console.log(documentHeight);

var viewportHeight = window.innerHeight;
console.log(viewportHeight);

var bodyHeight = document.body.offsetHeight;
console.log(bodyHeight);

var clientHeight = document.documentElement.clientHeight;
console.log(clientHeight);

window.addEventListener('scroll', function() {
    var scrollTop = window.pageYOffset || document.documentElement.scrollTop;
    var scrollHeight = document.documentElement.scrollHeight;
    var clientHeight = document.documentElement.clientHeight;

    if (scrollTop + clientHeight >= scrollHeight) {
        // 用户滚动到了页面底部，加载更多内容
        loadMoreContent();
    }
});

function loadMoreContent() {
    // 模拟加载更多内容的操作
    console.log('Loading more content...');
}