DBAdapt

TDataAdapterFieldValidateValueEvent is the type for event handlers that let you validate a value before it is assigned to a dataset adapter field. 

Sender is the dataset adapter field component. 

Field is the field component that this adapter field represents. 

Value is the interface for the value or set of values to validate. It represents the value that the current request supplies. 

Handled returns an indication of whether the event handler validated the new Value. If Handled returns true, the new value is considered valid, and the adapter then updates this field's value. Setting Handled to false indicates that the new value has not been validated one way or the other, not that the value has been found invalid. To indicate that the value is invalid, the event handler should raise an exception. 

Procedural types 

Creating events