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property Calculated: Boolean read GetCalculated write SetCalculated default False;


__property bool Calculated = {read=GetCalculated, write=SetCalculated, default=0};


Type Visibility Source Unit Parent
property public
Data.DB TField


Determines whether the value of the field is calculated by the OnCalcFields event handler of its dataset.

Use Calculated to determine if the field is a calculated field. When Calculated is True and the OnCalcFields event occurs, the OnCalcFields event handler updates the value of the field. The default value is False.

The value of a Calculated field is not stored in or retrieved from the physical tables underlying a dataset. Instead, calculated fields are calculated for each record in the table by the dataset's OnCalcFields event handler, which typically uses expressions involving values from other fields in the record to generate a value for each calculated field.

For example, a dataset might have non-calculated fields for Quantity and UnitPrice, and a calculated field for ExtendedPrice, which would be calculated by multiplying the values of the Quantity and UnitPrice fields in an OnCalcFields event handler.

Note: Do not change the setting of Calculated in application code. Calculated is automatically set to True by the Fields editor at design time if a field's value is specified as calculated.

Note: Do not confuse the Calculated property with the InternalCalcField property of a field definition. The value of a calculated field is computed in the OnCalcFields event handler. The value of an internally calculated field is computed by the SQL server or the Borland Database Engine.

See Also