Get Sheet By Name

I'm trying to get the following formula to work:

function setDataValid(range, sourceRange) {
  var rule = SpreadsheetApp.newDataValidation().requireValueInRange(sourceRange, true).build();
  range.setDataValidation(rule);
}

function onEdit() {
  var aCell = SpreadsheetApp.getActiveSheet().getActiveCell();
  var aColumn = aCell.getColumn();
  
  if (aColumn == 2 && SpreadsheetApp.getActiveSheet().getName() == 'Local' ) {
    var range = SpreadsheetApp.getActiveSheet().getRange(aCell.getRow(), aColumn + 1);
    var sourceRange = SpreadsheetApp.getActiveSpreadsheet().getRangeByName(aCell.getValue());
    setDataValid(range, sourceRange)
  }
}

When debugging onEdit() it shows that sourceRange in setDataValid(range, sourceRange) is null. As the range is in my sheet 'Local' I'm trying to change the getActiveSpreadsheet() to a get spreadsheet by name. Anyone who can help ?

Use get sheet by name on the spreadsheet:

var sheet = SpreadsheetApp.getActive().getSheetByName('Local')

Its very simple just get the sheet by name, the syntax is as follows as per the documentation.

    var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Expenses");

Please check the statement

var sourceRange = SpreadsheetApp.getActiveSpreadsheet().getRangeByName(aCell.getValue());

This should be the one returning null. For the cause look at the official documentation here.

var sourceRange = SpreadsheetApp.getActiveSpreadsheet().getRangeByName('Local!TaxRates')

should get the range.