Is it possible protect cells and ranges in google sheets after data entry using app script?

Question

Is it possible protect cells and ranges in google sheets after first data entry using app script? I am new to the script game. I use a drop down list and need to lock the cell / range data after the data change.

Answer 1

Using onEdit simple trigger (https://developers.google.com/apps-script/guides/triggers/) you can detect the modify and with methods of Class Protection you can lock a range of cells (https://developers.google.com/apps-script/reference/spreadsheet/protection).