Excle set the drop-down table, but the drop-down arrow option was not found.
"Data/Validity/Settings"; To select a sequence from the Allow drop-down list, two check boxes will be selected on the right, one is to ignore null values, and the other is to provide a drop-down arrow. After selecting both, enter your preset selection criteria in the source, such as Shanghai, Beijing, Xi 'an, etc. , separated by English commas, confirm the exit.