This type of client script runs when the list editor changes a cell value. Script runs when a particular field value on a list changes. Applies to all records selected.

In onCellEdit() client script we will get OOB parameters/Objects. Let me explain you each object in details.

Request you to watch it for better understanding.

A. sysIDs: It consist an array of the sys_ids for all items being edited.

B. table: The table of the items being edited.

C. oldValues: The old values of the cells being edited.

D. newValue: The new value for the cells being edited.

E. callback: A callback that continues the execution of any other related cell edit scripts.

If true is passed as a parameter, the other scripts are executed or the change is committed if there are no more scripts. If false is passed as a parameter, any further scripts are not executed and the change is not committed.

Now lets take a look on real word example

Real World Scenario

Requirement: Prevent state being edited from list view of incident if state marked as Resolved or Closed.

Solution: create onCellEdit client script and write below code.

function onCellEdit(sysIDs, table, oldValues, newValue, callback){
var saveAndClose = true;

if(newValue == 6) { //Resolved
alert("You cannot change the State to 'Resolved' from a list");
saveAndClose = false;
}
if(newValue == 7) { //Closed
alert("You cannot change the State to 'Closed' from a list");
saveAndClose = false;
}
callback(saveAndClose);
}