Learn Basics of Google Apps Scripts

// The code below makes the 2nd sheet active in the active spreadsheet.
var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();

// The code below creates a new spreadsheet "Finances" and logs the URL for it
var ssNew = SpreadsheetApp.create("Finances");
Logger.log(ssNew.getUrl());
// The code below creates a new spreadsheet "Finances" with 50 rows and 5 columns and logs the
// URL for it
var ssNew = SpreadsheetApp.create("Finances", 50, 5);
Logger.log(ssNew.getUrl());

// The code below opens a spreadsheet using its id and logs the name for it.
// Note that the spreadsheet is NOT physically opened on the client side.
// It is opened on the server only (for modification by the script).
var ss = SpreadsheetApp.openByUrl(
    'https://docs.google.com/spreadsheets/d/abc1234567/edit');
Logger.log(ss.getName());

// The code below opens a spreadsheet using its URL.
var ss = SpreadsheetApp.openById("abc1234567");
Logger.log(ss.getName());

// The code below logs the URL for the active spreadsheet.
Logger.log(SpreadsheetApp.getActive().getUrl());
// The code below logs the URL for the active spreadsheet.
Logger.log(SpreadsheetApp.getActiveSpreadsheet().getUrl());
// The code below logs the background color for the active range.
var colorObject = SpreadsheetApp.getActiveRange().getBackgroundObject();
// Assume the color has ColorType.RGB.
Logger.log(colorObject.asRgbColor().asHexString());
var selection = SpreadsheetApp.getSelection();
var currentCell = selection.getCurrentCell();

var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];

// This logs the value in the very last cell of this sheet
var lastRow = sheet.getLastRow();
var lastColumn = sheet.getLastColumn();
var lastCell = sheet.getRange(lastRow, lastColumn);
Logger.log(lastCell.getValue());

// This example assumes there is a sheet named "first"
var ss = SpreadsheetApp.getActiveSpreadsheet();
var first = ss.getSheetByName("first");
Logger.log(first.getMaxRows());
// This example assumes there is a sheet named "first"
var ss = SpreadsheetApp.getActiveSpreadsheet();
var first = ss.getSheetByName("first");
Logger.log(first.getMaxColumns());

var ss = SpreadsheetApp.getActiveSpreadsheet();
ss.insertSheet('My New Sheet');
//Inserts a new sheet into the spreadsheet with the given name and uses optional advanced arguments. The new sheet becomes the active sheet.
var ss = SpreadsheetApp.getActiveSpreadsheet();
var templateSheet = ss.getSheetByName('Sales');
ss.insertSheet('My New Sheet', {template: templateSheet});

// Reading range
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];
// When the "numRows" argument is used, only a single column of data is returned.
var range = sheet.getRange(1, 1, 3);
var values = range.getValues();

// Prints 3 values from the first column, starting from row 1.
for (var row in values) {
  for (var col in values[row]) {
    Logger.log(values[row][col]);
  }
}

// Reading Data Range

var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];

// This represents ALL the data
var range = sheet.getDataRange();
var values = range.getValues();

// This logs the spreadsheet in CSV format with a trailing comma
for (var i = 0; i < values.length; i++) {
  var row = "";
  for (var j = 0; j < values[i].length; j++) {
    if (values[i][j]) {
      row = row + values[i][j];
    }
    row = row + ",";
  }
  Logger.log(row);
// Appends a new row with 3 columns to the bottom of the current
// data region in the sheet containing the values in the array.
  var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];
sheet.appendRow(["a man", "a plan", "panama"]);
}

// The code below gets the values for the range C2:G8
// in the active spreadsheet.  Note that this is a JavaScript array.
var values = SpreadsheetApp.getActiveSheet().getRange(2, 3, 6, 4).getValues();
Logger.log(values[0][0]);
// The code below gets the displayed values for the range C2:G8
// in the active spreadsheet.  Note that this is a JavaScript array.
var values = SpreadsheetApp.getActiveSheet().getRange(2, 3, 6, 4).getDisplayValues();
Logger.log(values[0][0]);

// Menus & sub menus
function onOpen() {
  var ui = SpreadsheetApp.getUi();
  // Or DocumentApp or FormApp.
  ui.createMenu('Custom Menu')
      .addItem('First item', 'menuItem1')
      .addSeparator()
      .addSubMenu(ui.createMenu('Sub-menu')
          .addItem('Second item', 'menuItem2'))
      .addToUi();
}

function menuItem1() {
  SpreadsheetApp.getUi() // Or DocumentApp or FormApp.
     .alert('You clicked the first menu item!');
}

function menuItem2() {
  SpreadsheetApp.getUi() // Or DocumentApp or FormApp.
     .alert('You clicked the second menu item!');
}

function onOpen() {
  SpreadsheetApp.getUi() // Or DocumentApp or SlidesApp or FormApp.
      .createMenu('Custom Menu')
      .addItem('Show sidebar', 'showSidebar')
      .addToUi();
}

function showSidebar() {
  var html = HtmlService.createHtmlOutputFromFile('Page')
      .setTitle('My custom sidebar');
  SpreadsheetApp.getUi() // Or DocumentApp or SlidesApp or FormApp.
      .showSidebar(html);
}

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