// ==UserScript==// @name              一个返回顶部和到达底部的按钮// @name:en           a button which can back to the top and go to the bottom// @namespace         http://mofiter.com/// @version           0.3// @description       在网页上添加一个按钮，可以快速返回顶部和到达底部，有滑动效果// @description:en    Add a button for all websites which can back to the top and go to the bottom,and there is a sliding effecct.// @author            mofiter// @create            2018-07-22// @lastmodified      2018-08-24// @resource          up_button_icon https://coding.net/u/mofiter/p/public_files/git/raw/master/back_to_top_button.png// @resource          down_button_icon https://coding.net/u/mofiter/p/public_files/git/raw/master/go_to_bottom_button.png// @require           https://cdn.bootcss.com/jquery/1.12.4/jquery.min.js// @include           http*://*/*// @grant             GM_info// @grant             GM_getResourceURL// @noframes// ==/UserScript==(function() {'use strict';var $ = $ || window.$;var canScrollMouseOver = false; //当鼠标在按钮上，但未点击时，页面能否自动滚动，true 为可以自动滚动，false 为不能自动滚动，可修改var opacityMouseLeave = 0.5; //当鼠标不在按钮上时，按钮的不透明度，从 0.0（完全透明）到 1.0（完全不透明），可修改var opacityMouseEnter = 0.8; //当鼠标在按钮上时，按钮的不透明度，从 0.0（完全透明）到 1.0（完全不透明），可修改var clickScrollTime = 500; //点击按钮时，网页滚动到顶部或底部需要的时间，单位是毫秒，可修改var needScrollTime; //网页可以自动滚动时，滚动需要的时间，由网页高度计算得出，这样不同网页都会匀速滚动var isClicked = false; //按钮是否被点击var initialHeight = 0; //网页向底部滚动时，需要滚动的距离var scrollAction = 'undefined';var scrollDirection = "down"; //网页滚动方向，down 为向下，up 为向上var loadTimes = 0; //网页中动态增加数据的次数var maxLoadTimes = 10; //最大的动态增加数据的次数（可修改），如果动态增加数据的次数超过这个值，则说明当前网页不适合执行此脚本，建议将其加入排除的网站当中var goTopBottomButton = document.createElement("div");goTopBottomButton.className = "goTopBottomButton";goTopBottomButton.innerHTML = "<img class='toggleButton' style='width:35px;height:35px;display:block;cursor:pointer;'></img>"; //图片的宽和高可修改，原始图片宽高均为 40pxgoTopBottomButton.style.position = "fixed";goTopBottomButton.style.zIndex = 10000;goTopBottomButton.style.bottom = "50px"; //距离网页底部 50px，可修改goTopBottomButton.style.right = "30px"; //距离网页右边 30px，可修改var toggleButton = goTopBottomButton.lastChild;toggleButton.style.opacity = opacityMouseLeave; //按钮初始不透明度toggleButton.src = GM_getResourceURL("down_button_icon"); //按钮初始显示向下的图片document.getElementsByTagName("body")[0].appendChild(goTopBottomButton);/*按钮事件开始*/toggleButton.addEventListener("mouseenter",function() { //鼠标移入时不透明度改变，如果 canScrollMouseOver 为 true，则网页可以自动滚动isClicked = false;if (canScrollMouseOver) {if (scrollDirection == "up") {needScrollTime = getScrollTop() * 10;$('html,body').animate({scrollTop:'0px'},needScrollTime);} else {initialHeight = $(document).height();var restHeight = $(document).height() - getScrollTop();needScrollTime = restHeight * 10;$('html,body').animate({scrollTop:initialHeight},needScrollTime,continueToBottom);}}toggleButton.style.opacity = opacityMouseEnter;})toggleButton.addEventListener("mouseleave",function() { //鼠标移出时不透明度改变，如果 canScrollMouseOver 为 true，并且按钮未被点击，停止网页自动滚动的动画if (canScrollMouseOver && !isClicked) {$('html,body').stop();}toggleButton.style.opacity = opacityMouseLeave;})toggleButton.addEventListener("click",function() { //点击按钮时，网页滚动到顶部或底部isClicked = true;if (canScrollMouseOver) {$('html,body').stop();}if (scrollDirection == "up") {$('html,body').animate({scrollTop:'0px'},clickScrollTime);} else {initialHeight = $(document).height();$('html,body').animate({scrollTop:initialHeight},clickScrollTime,continueToBottom);}})/*按钮事件结束*//*页面滚动监听*/document.onscroll = function() {if (scrollAction == 'undefined') {scrollAction = window.pageYOffset;}var diffY = scrollAction - window.pageYOffset;scrollAction = window.pageYOffset;if (diffY < 0) {changeDirection("down");} else if (diffY > 0) {changeDirection("up");}if (getScrollTop() == 0) {changeDirection("down");}if (getScrollTop() + $(window).height() >= $(document).height()) {changeDirection("up");}}function changeDirection(direction) { //改变按钮方向scrollDirection = direction;toggleButton.src = GM_getResourceURL(direction + "_button_icon");}function getScrollTop() { //获取垂直方向滑动距离var scrollTop = 0;if (document.documentElement && document.documentElement.scrollTop) {scrollTop = document.documentElement.scrollTop;} else if (document.body) {scrollTop = document.body.scrollTop;}return scrollTop;}function continueToBottom() { //判断页面是否继续下滑（主要是为了处理网页动态增加数据导致网页高度变化的情况）var currentHeight = $(document).height();if (initialHeight != currentHeight) {if (loadTimes >= maxLoadTimes) {$('html,body').stop();alert(" 本网站有太多的异步请求，不适合执行脚本《" + GM_info.script.name + "》，建议加入排除网站当中，具体方法请查看脚本主页");loadTimes = 0;return;}loadTimes ++;initialHeight = currentHeight;$('html,body').animate({scrollTop:initialHeight},1000,continueToBottom);}}})();