Image Viewer

inject this script into any page, and right-click on the image you want to view full-size

当前为 2017-06-11 提交的版本,查看 最新版本

您需要先安装一个扩展,例如 篡改猴Greasemonkey暴力猴,之后才能安装此脚本。

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

您需要先安装一个扩展,例如 篡改猴暴力猴,之后才能安装此脚本。

您需要先安装一个扩展,例如 篡改猴Userscripts ,之后才能安装此脚本。

您需要先安装一款用户脚本管理器扩展,例如 Tampermonkey,才能安装此脚本。

您需要先安装用户脚本管理器扩展后才能安装此脚本。

(我已经安装了用户脚本管理器,让我安装!)

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

(我已经安装了用户样式管理器,让我安装!)

// ==UserScript==
// @name       Image Viewer
// @namespace  https://gist.github.com/bradenbest/04bd0fc2d57ec650449f
// @version    1.6.0
// @description  inject this script into any page, and right-click on the image you want to view full-size
// @copyright  2014 - 2017, Braden Best
// ==/UserScript==

const firefox = /Firefox/i.test(navigator.userAgent);

function mk_node({
    name = "span",
    props = [],
    styles = [],
    events = [],
    extra = null
} = {}){
    let el = document.createElement(name);

    props.forEach(function([name, value]){
        el[name] = value;
    });

    styles.forEach(function([name, value]){
        el.style[name] = value;
    });

    events.forEach(function([name, callback]){
        el.addEventListener(name, function(ev){
            callback(ev, el);
        });
    });

    if(extra)
        extra(el);

    return el;
}

function mk_img(url){
    return mk_node({
        name: "img",
        props: [
            ["src",        url],
            ["className",  "img_viewer"],
            ["draggable",  "false"],
            ["dragging",   0],
            ["mousepos",   [0,0]],
            ["tabIndex",   0]
        ],
        styles: [
            ["position",  "absolute"],
            ["left",      "0px"],
            ["top",       (80 + document.body.scrollTop) + "px"],
            ["zIndex",    "2147483647"]
        ],
        events: [
            ["mousedown", function(ev, self){
                self.dragging = firefox
                    ? !self.dragging
                    : 1;

                self.mousepos[0] = (ev.clientX || ev.pageX);
                self.mousepos[1] = (ev.clientY || ev.pageY);
            }],
            ["mouseup", function(unused, self){
                if(firefox)
                    return false;

                self.dragging = 0;
            }],
            ["mousemove", function(ev, self){
                let curX = (ev.clientX || ev.pageX);
                let curY = (ev.clientY || ev.pageY);
                let diffX = curX - self.mousepos[0];
                let diffY = curY - self.mousepos[1];

                if(!self.dragging || (!diffX && !diffY))
                    return false;

                self.mousepos = [curX, curY];
                self.style.left = parseInt(self.style.left) + diffX + "px";
                self.style.top  = parseInt(self.style.top)  + diffY + "px";
            }],
            ["keydown", function(ev, self){
                let dispatch = ({
                    "ArrowUp":    ["height", -10],
                    "ArrowDown":  ["height", +10],
                    "ArrowLeft":  ["width",  -10],
                    "ArrowRight": ["width",  +10]
                })[ev.key] || ["width", 0];

                self[dispatch[0]] = +self[dispatch[0]] + dispatch[1];
            }]
        ]
    });
}

function mk_img_helper({img, img_helper_link}){
    let el = mk_node({
        name: "div",
        props: [
            ["innerHTML", "Click here to close image"],
            ["className", "img_viewer"]
        ],
        styles: [
            ["position",     "fixed"],
            ["left",         "0px"],
            ["top",          "0px"],
            ["margin",       "0"],
            ["padding",      "5px 0"],
            ["width",        "100%"],
            ["height",       "50px"],
            ["background",   "#fff"],
            ["borderBottom", "1px solid #ccc"],
            ["color",        "#000"],
            ["fontSize",     "12px"],
            ["textAlign",    "center"],
            ["zIndex",       "2147483647"]
        ],
        events: [
            ["click", function(unused, unused2){
                document.body.removeChild(img);
                document.body.removeChild(el);
                document.body.removeChild(img_helper_link);
            }]
        ]
    });

    return el;
}

function mk_img_helper_link(url){
    return mk_node({
        name: "a",
        props: [
            ["innerHTML", "Direct URL"],
            ["href", url],
            ["target", "_blank"],
            ["className", "img_viewer"]
        ],
        styles: [
            ["margin", "0"],
            ["padding", "0"],
            ["background", "#fff"],
            ["borderBottom", "1px solid #ccc"],
            ["display", "block"],
            ["width", "100%"],
            ["height", "20px"],
            ["position", "fixed"],
            ["left", "0"],
            ["top", "50px"],
            ["fontSize", "12px"],
            ["textAlign", "center"],
            ["zIndex", "2147483647"]
        ]
    });
}

function mk_img_group(url){
    let img = mk_img(url);
    let img_helper_link = mk_img_helper_link(url);
    let img_helper = mk_img_helper({img, img_helper_link});

    [img, img_helper, img_helper_link].forEach(function(node){
        document.body.appendChild(node);
    });

    return { img, img_helper, img_helper_link };
}

function clear(){
    [...document.querySelectorAll(".img_viewer")]
        .forEach(function(viewer){
            document.body.removeChild(viewer);
        });
}

function init(){
    [...document.querySelectorAll("img")].forEach(function(img){
        img.addEventListener("contextmenu", function(ev){
            mk_img_group(img.src);
            ev.preventDefault();
        });
    });

    document.body.addEventListener("mouseup", function(ev){
        if(firefox)
            return false;

        [...document.querySelectorAll(".img_viewer")]
            .forEach(function(viewer){
                viewer.dragging = 0;
            });
    });

    document.body.addEventListener("keydown", function(ev){
        let dispatch = ({
            "Escape":  clear,
            "Control": init
        })[ev.key] || (()=>null);

        dispatch();
    });
}

init();
console.log("Image Viewer started up.");
console.log("Try right-clicking an image");