beforeChange

fires before changing the value of a control

beforeChange: (value: string) => boolean | void;

Parameters:

• value: string - the value to be set for the control

Returns:

Return false to prevent changing the value of the control; otherwise, true.

Example

form.getItem("textarea").events.on("beforeChange", function(value) {
    console.log("beforeChange", value);
    return true;
});

Change log: The event was added in v8.0