原生js编写一个图片幻灯片效果代码-html代码-BFW代码库

原生js编写一个图片幻灯片效果代码

代码语言：html

所属分类：幻灯片

代码描述：原生js编写一个图片幻灯片效果代码

下面为部分代码预览，完整代码请点击下载或在bfwstudio webide中打开

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">

    <script>
    function animation(obj, target, callback) {//obj要实现的那个元素， target目标位置
    clearInterval(obj.timer);//清除以前的定时器，只保留当前的
    obj.timer = setInterval(function () {
        var step = (target - obj.offsetLeft) / 10;
        step = step > 0 ? Math.ceil(step) : Math.floor(step);
        if (obj.offsetLeft == target) {
            clearInterval(obj.timer);
            //回调函数
            callback && callback();
        } else {
            obj.style.left = obj.offsetLeft + step + 'px';
        }
    }, 15);
}

        window.addEventListener('load', function () {
    var banner = document.querySelector('.banner');
    var prev = document.querySelector('.prev');
    var next = document.querySelector('.next');
    var circle = document.querySelector('.gd');
    var bannerWidth = banner.offsetWidth;
    var ul = banner.querySelector('ul');
    var num = 0;

    //鼠标移动盒子内让按钮显示
    banner.addEventListener('mouseenter', function () {
        prev.style.display = 'block';
        next.style.display = 'block';
        clearInterval(autoPlay);
        autoPlay = null;//清除定时器
    })
    banner.addEventListener('mouseleave', function () {
        prev.style.display = 'none';
        next.style.display = 'none';
        autoPlay = setInterval(function () {
            //手动调用点击事件
            next.click();
        }, 2000);
    });

    //设置ul的宽度
    var nums = ul.children.length;
    ul.style.width = nums * bannerWidth + 'px';

    //动态创建底部小圆点
    for (var k = 0; k < nums; k++) {
        let i = document.createElement('i');
        circle.appendChild(i);
        i.setAttribute('index', k);
        i.addEventListener('click', function () {
            num = this.getAttribute('index');
            animation(ul, -num * bannerWidth);
            currents();
        });
    }


    //为按钮prev，next加事件
    circle.children[num].className = 'current';
    //判断有没有执行完动画
    var flag = true;
    next.addEventListener('click', function () {
        if (flag) {
            flag = false;
            if (num == nums - 1) {
                animation(ul, 0);
                num = 0;
                flag = true;
            } else {
                num++;
                animation(ul, -num * bannerWidth, function () {
                    flag = true;
                });
            }
            currents();
        }
    });

    prev.addEventListener('click', function () {
        if (flag) {
            flag = false;
            if (num == 0) {
                animation(ul, -nums * bannerWidth - 1);
                num = nums - 1;
                flag = true;
            } else {
                num--;
                animation(ul, -num * bannerWidth, function () {
                    flag = true;
                });
            }
            currents();
        }
    });


    function currents() {
        for (var a = 0; a < nums; a++) {
            circle.children[a].className = '';
        }
        circle.children[num].className = 'current';
    }
    //无缝播放
    var li = ul.children[0].cloneNode(true);
    ul.appendChild(li);

    //自动播放
    var autoPla.........完整代码请登录后点击上方下载按钮下载查看