DAC for MySQL
TDataSet.Properties.AutoCalcFields | Previous Next |
Determines when the OnCalcFields event is triggered.
Syntax:
property AutoCalcFields: Boolean;
Description:
Set AutoCalcFields to control when the OnCalcFields event is triggered to update
calculated fields during dataset processing. A calculated field is one that derives its value from the
values of one or more fields in the active record, sometimes with additional processing.
When AutoCalcFields is True (the default), OnCalcFields is triggered when:
- The dataset is opened.
- The dataset is put into dsEdit state.
- Focus moves from one visual control to another, or from one column to another in a data-aware
grid and modifications were made to the record.
- A record is retrieved from a database.
If an application permits users to change data, OnCalcFields is frequently triggered. In
these cases an application may set AutoCalcFields to False to reduce the frequency with
which AutoCalcFields is called. When AutoCalcFields is False, OnCalcFields
is not called when changes are made to individual fields within a record.