take last row of datarange code example

Example 1: google script last row

var cells = sheetInput.getRange("a:a").getValues();//Gets all cells in col A.
   
    var filter = cells.filter((cell) => cell != "");//filters out the blanks.
    var lr = parseInt(filter.length) + 1;//This is the Last Row.
    
    Logger.log(lr);

Example 2: apps script get last row with data

var cur_ss = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  var data = cur_ss.getDataRange().getValues();
  
  var Avals = cur_ss.getRange("B9:B").getValues();
  var Alast = Avals.filter(String).length;
  return (Alast + 9);