Calculated Fields - How to

Simple question. How do I define and access a calculated field in a table.

I have two field values i want to multiply, with the total going in the calculated field.

Thanks.
DougBennettAsked:
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pc_melsaConnect With a Mentor Commented:
To add calculated fields, use the field editor, which is accessed by double clicking the TTable Component. Select the Define button, you'll nee to supply a new field name and the data type of the field.
Delphi 2,3 executes the procedure in the OnCalcFields event handler whenever there is need to recalculated field.
While in the OnCalcFields event handler, the dataset will be in dsCalcFields state.

Here is the example :

procedure MyForm.InventoryCalcFields(Dataset: TDataSet) ;
VAR
   CurrentPrice, LbsPerYard, YardsInStock : double ;
BEGIN
   CurrentPrice := MyTable['CostPerYard'].AsFloat ;
   LbsPerYard   := MyTable['LbsPerYard'].AsFloat ;
   YardsInStock := MyTable['CubicYards'].AsFloat ;

    // Assign value to the fields that are calculated
   MyTable['MarketValue'].AsFloat := CurrentPrice * YardsInStock ;
   MyTable['LbsInStock'].AsFloat := LbsPerYard * YardsInStock ;
END ;


Hope you'll satisfied.
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pc_melsaCommented:
Thank you very much !
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