How do I convert string cell value of a number into a number increment by 1?

I am trying to fetch the last row's row id (located in the first column) to increment it by one once there is a new row added. However I am not sure on how to convert the string into a number to increment by 1

What I tried:

  var url = "";
  var ss = SpreadsheetApp.openByUrl(url);
  var ws = ss.getSheetByName("Data");

  var rowID = ws.getRange(ws.getLastRow(), 1).getValues().toString().parseInt()+1; 
  console.log(rowID);

Which is not a function based on the log.

If the values of your id is 1, 2, 3,,, , how about the following modification?

From:

var rowID = ws.getRange(ws.getLastRow(), 1).getValues().toString().parseInt()+1;

To:

var rowID = (parseInt(ws.getRange(ws.getLastRow(), 1).getValue(), 10) || 0) + 1;

or

var rowID = (Number(ws.getRange(ws.getLastRow(), 1).getValue()) || 0) + 1;

or, in the event the value in the last row is known to always be a number or a blank, the following modification might be able to be used.

var rowID = ws.getRange(ws.getLastRow(), 1).getValue() + 1;

Reference:

• parseInt()