Scroll to Top

Add a button to scroll to the top of the page

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @name         Scroll to Top
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Add a button to scroll to the top of the page
// @author       Irushia
// @license      MIT
// @match        *://*/*
// @exclude      http*://*.youtube.com/*
// @icon         data:image/png;base64,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
// @run-at       document-start
// @grant        GM_registerMenuCommand
// ==/UserScript==

(function () {
    document.addEventListener("scroll", insertButton, {
        capture: true,
        once: true,
    });

    function insertButton() {
        const SELECTOR_ID = "scrollTop-btn";
        const btn = document.createElement("button");
        btn.id = SELECTOR_ID;
        Object.assign(btn.style, {
            position: "fixed",
            cursor: "pointer",
            bottom: 0,
            left: "20%",
            visibility: "hidden",
            opacity: 0.5,
            width: "40%",
            height: "40px",
            border: "none",
            outline: "none",
            "z-index": 1,
            "border-radius": "100% 100% 0 0",
            "font-size": "16px",
            "background-color": "rgba(0,0,0,.3)",
            "box-shadow":
            "0 16px 24px 2px rgba(0, 0, 0, .14), 0 6px 30px 5px rgba(0, 0, 0, .12), 0 8px 10px -5px rgba(0, 0, 0, .4)",
        });
        btn.addEventListener("click", () => {
            window.scrollTo({
                top: 0,
                behavior: "smooth", // "instant",
            });
        });
        const arrow = document.createElement("span");
        Object.assign(arrow.style, {
            border: "solid white",
            "border-width": "0 3px 3px 0",
            display: "inline-block",
            padding: "4px",
            "vertical-align": "middle",
            transform: "rotate(-135deg)",
        });
        btn.append(arrow);
        document.body.append(btn);
        const cssRule = `
            #${SELECTOR_ID}:hover {
                opacity: 1 !important;
                background-color: rgba(0,0,0,.6) !important;
                }
        `;
        const styleElement = document.createElement("style");
        styleElement.textContent = cssRule;
        document.head.appendChild(styleElement);

        const scrollTop_btn = document.getElementById(SELECTOR_ID);
        let sOld;
        window.addEventListener("scroll", () => {
            const sCurr = document.documentElement.scrollTop > window.innerHeight / 4;
            if (sCurr == sOld) return;
            sOld = sCurr;
            scrollTop_btn.style.visibility = sCurr ? "visible" : "hidden";
        });
    }
})();