Automated task reminder in Google Spreadsheet: Automatically send deadline notifications via email.

function sendTaskReminder() {
  // Get the active spreadsheet
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  
  // Get the sheet named "Tasks"
  var sheet = ss.getSheetByName("Tasks");
  
  // Check if the sheet exists
  if(sheet === null) {
    Logger.log("The sheet named 'Tasks' was not found.");
    return;
  }
  
  // Get the range where tasks and due dates are stored (in this example, Column A for tasks, Column B for due dates)
  var tasks = sheet.getRange("A2:B10").getValues();
  
  // Get today's date and calculate tomorrow's date
  var today = new Date();
  var tomorrow = new Date(today.getTime() + (24 * 60 * 60 * 1000)); // 1 day later (24 hours * 60 minutes * 60 seconds * 1000 milliseconds)
  
  // Check each task
  for (var i = 0; i < tasks.length; i++) {
    var taskName = tasks[i][0];
    var dueDate = new Date(tasks[i][1]);
    
    // If the due date is tomorrow, send an email
    if (dueDate.toDateString() === tomorrow.toDateString()) {
      var email = "your_email@example.com"; // Please change this to your own email address
      var subject = "Task Reminder: " + taskName;
      var body = "The following task is due tomorrow: " + taskName + " (Due Date: " + dueDate.toDateString() + ")";
      MailApp.sendEmail(email, subject, body);
    }
  }
}

// MIT License
// Copyright (c) 2023 [ANJI]
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
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// copies of the Software, and to permit persons to whom the Software is
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// SOFTWARE.