【JavaScript】分享一個定時到網站上籤到/簽退的JS腳本

之前介紹過使用temperMonkey屏蔽CSDN廣告的方法，主要就是要針對性地分析網站結構，然後用代碼去改變或者操作DOM。今天也一樣，我們需要觀察網頁結構，找到我們要操作的按鈕，觸發他的click事件就可以了。下面以公司打卡簽到的網站爲例，做一些壞壞的事情。本文讀者最好有一定的HTML和JavaScript基礎。

首先，想象一下你去簽到需要做什麼：

1. 打開網站
2. 登陸
3. 點擊“簽到”按鈕

然後每一步我們都可以讓代碼幫我們去做。

0. 如何定時

這段代碼是核心，就是根據當前時間和設定的時間做差值，來確定定時器的值
看懂這段代碼，後面的就都容易了。都是在利用定時器觸發callback。

// user setting
const SIGN_IN_TIME = "09:30:00"; // 簽到時間
const SIGN_OUT_TIME = "20:00:00"; // 簽退時間

// code implementation
logTime("code start running");
const now = new Date();
const today = now.getFullYear() + "-" + (now.getMonth() + 1) + "-" + now.getDate();
var signInTime = +new Date(`${today} ${SIGN_IN_TIME}`);
logTime("signInTime", new Date(signInTime));
var signOutTime = +new Date(`${today} ${SIGN_OUT_TIME}`);
logTime("signOutTime", new Date(signOutTime));
// diff in or out
if (now > signInTime && now < signOutTime) {
    // ready to sign out for today
    console.log("Seconds to sign out for today: " + (signOutTime - now) / 1000);
    setTimeout(callback, signOutTime - now);
} else {
    // ready to sign in for tomorrow
    signInTime = +signInTime + 60 * 60 * 24 * 1000;
    console.log("Seconds to sign in for tomorrow: " + (signInTime - now) / 1000);
    setTimeout(callback, signInTime - now);
}

function logTime(str, time = new Date()) {
    console.log(`${str} -> ${time.getHours()}:${time.getMinutes()}:${time.getSeconds()}`);
}

1. 定時自動打開網站

因爲大多數網站都有，“長時間未操作-自動退出”的設置。所以我們要在需要打卡的時候再打開網站。
在電腦本地跑一個程序，使用定時器。這裏跑一個node程序：

const open = require('open');
logTime("Start Runing");

// user setting
const SIGN_IN_TIME = "09:30:00";
const SIGN_OUT_TIME = "20:20:00";

// code implementation
const openBrowser = async () => {
    await open('http://172.10.80.42');
};
logTime("code start running");
const now = new Date();
const today = now.getFullYear() + "-" + (now.getMonth() + 1) + "-" + now.getDate();
var signInTime = +new Date(`${today} ${SIGN_IN_TIME}`);
logTime("signInTime", new Date(signInTime));
var signOutTime = +new Date(`${today} ${SIGN_OUT_TIME}`);
logTime("signOutTime", new Date(signOutTime));
// diff in or out
if (now > signInTime && now < signOutTime) {
    // ready to sign out for today
    console.log("Seconds to sign out for today: " + (signOutTime - now) / 1000);
    setTimeout(openBrowser, signOutTime - now);
} else {
    // ready to sign in for tomorrow
    signInTime = +signInTime + 60 * 60 * 24 * 1000;
    console.log("Seconds to sign in for tomorrow: " + (signInTime - now) / 1000);
    setTimeout(openBrowser, signInTime - now);
}

function logTime(str, time = new Date()) {
    console.log(`${str} -> ${time.getHours()}:${time.getMinutes()}:${time.getSeconds()}`);
}

2. 自動登錄

這個重點還是在於找到需要填入內容的DOM元素

(function() {
    'use strict';
    // login
    document.querySelector("#loginid").value = "用戶名";
    document.querySelector("#userpassword").value = "密碼";
    document.querySelector("#login").click();
})();

3. 定時點擊按鈕

這一步最重要的是要準確找到按鈕，檢查元素慢慢查找吧。
其次，設定好籤到和簽退的時間，只有固定時間纔會自動簽到，防止每次登陸進來自動簽到或簽退，這樣太頻繁被發現。

(function() {
  'use strict';

  // user setting
  const SIGN_IN_TIME = "09:00:00";
  const SIGN_OUT_TIME = "21:00:00";

  // code implementation
  logTime("code start running");
  const now = new Date();
  const today = now.getFullYear()+"-"+(now.getMonth()+1)+"-"+now.getDate();
  var signInTime = +new Date(`${today} ${SIGN_IN_TIME}`);
  logTime("signInTime", new Date(signInTime));
  var signOutTime = +new Date(`${today} ${SIGN_OUT_TIME}`);
  logTime("signOutTime", new Date(signOutTime));
  // diff in or out
  if(now > signInTime && now < signOutTime) {
      // ready to sign out for today
      console.log("Seconds to sign out for today: " + (signOutTime - now)/1000);
      setTimeout(signInorSignOut, signOutTime - now);
  } else {
      // ready to sign in for tomorrow
      signInTime = +signInTime + 60 * 60 * 24 * 1000;
      console.log("Seconds to sign in for tomorrow: " + (signInTime - now)/1000);
      setTimeout(signInorSignOut, signInTime - now);
  }

  // signInorSignOut
  function signInorSignOut(){
      logTime(`signInButton clicked!`);
      // 重點就在這兒了，找到網站的簽到按鈕#signInButton，並觸發他的點擊事件
      document.querySelector("#signInButton").click();
  }

  function logTime(str, time=new Date()){
    console.log(`${str} -> ${time.getHours()}:${time.getMinutes()}:${time.getSeconds()}`);
  }
})();

4. 結束

一套操作，打完收工。每天下班的時候，不管是提前溜還是晚點到。記得本地開一下程序：

node timer.js