Create a new sheet with a name based on the next month

Question

I have a script which creates a new sheet with a name based on month-year, like Oct-2017, automatically every new month.

But now I'd like to have a button, where I can create new sheets with the same structure, with names based on the MMM-yyyy.

My first script creates a new sheet only when the month changes, but now my intention is to be able to create it when I judge necessary by pressing that button. How to create a button is not a problem.

So, if before the sheet name was based on the following code,

function checkSheetName() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheetName = formatDate(); // load the current 'Month-Year'

  try {
    ss.setActiveSheet(ss.getSheetByName(sheetName)); // try to set 'sheetName' as active sheet
  } catch (e) { // if returns error,
    createNewMonthSheet(); // creates a new sheet
  }

function createNewMonthSheet() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheetName = formatDate(); // load the current 'Month-Year'  
  ss.insertSheet(sheetName, 2); // creates a new sheet on the left side, after 2 existing sheets
}

function formatDate() {
  var monthNames = ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"];
  var monthNumber = Utilities.formatDate(new Date(), 'GMT+12:00', "M");
  var yearNumber = Utilities.formatDate(new Date(), 'GMT+12:00', "yyyy");
  return monthNames[monthNumber-1]+'-'+yearNumber; 
}

now the code needs to use the Sheet Name as a reference for the new name, increasing the date and respecting a real calendar, so if the current sheet name is Dec-2017, the button will create a new sheet called Jan-2018. So no need anymore to be related to the new Date command like my previous code.

I started a new code, but I don't know how to create the var nameOfNextMonth :

function createNewSheet() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var currentMonth = ss.getActiveSheet().getName();
  var nameOfNextMonth = **[currentMonth+1]**;
  ss.setActiveSheet(ss.getSheetByName("template"));
  var newSheet = ss.duplicateActiveSheet();
  newSheet.activate();
  ss.moveActiveSheet(0);
  newSheet.setName(nameOfNextMonth);
}

Is that making any sense? Could anyone give me any idea how to proceed?

Answer 1

I didn't include any error handling (so make sure the active sheet has a name with the format mmm-yyyy), but see if this works

function createNewSheet() {
var monthNames = ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"];
var ss = SpreadsheetApp.getActiveSpreadsheet();
var curMonth = ss.getActiveSheet().getName().split("-")
var nextMonth = new Date(curMonth[1], monthNames.indexOf(curMonth[0])+1, 1);
var name = Utilities.formatDate(nextMonth, 'GMT+12:00', "MMM-yyyy")
ss.setActiveSheet(ss.getSheetByName("template"));
if(!ss.getSheetByName(name)){    
ss.duplicateActiveSheet().activate().setName(name)
ss.moveActiveSheet(0);
}
}

Answer 2

You can get next Months name by using standard new Date() , it will handle incrementing to the appropriate year and moding to the appropriate month.

Also, make sure to check if the worksheet by that name already exists or not

function createWorksheet()
{
  var monthNames = ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"];
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();

  var monthsToAdd = 1;
  var currentDate = new Date();
  currentDate.setMonth(currentDate.getMonth() + monthsToAdd);

  var sheetName = monthNames[currentDate.getMonth()]+"-"+currentDate.getFullYear();
  var sheetsArray = spreadsheet.getSheets();
  var creationFlag = false;
  //Logger.log(sheetsArray)
  for(var itr in sheetsArray)
  {
    if(sheetsArray[itr].getSheetName() == sheetName)
    {
      creationFlag = false;
      break;
    }
    else
      creationFlag = true;
  }

  if(creationFlag)
    spreadsheet.insertSheet(sheetName);

  if(!creationFlag)
    Logger.log("Worksheet Exists");
}//createWorksheet