API:Bde.DBTables.TBDEDataSet.Lookup
| [–] Properties | |
|---|---|
| Type: function | |
| Visibility: public | |
| Source: Bde.DBTables.pas Bde.DBTables.hpp
| |
| Unit: Bde.DBTables | |
| Parent: TBDEDataSet | |
Delphi
function Lookup(const KeyFields: string; const KeyValues: Variant;
const ResultFields: string): Variant; override;
C++
virtual System::Variant __fastcall Lookup(const System::UnicodeString KeyFields, const System::Variant &KeyValues, const System::UnicodeString ResultFields);
Description
Implements a virtual method to retrieve field values from a record that matches specified search values.
Bde.DBTables.TBDEDataSet.Lookup inherits from Data.DB.TDataSet.Lookup. All content below this line refers to Data.DB.TDataSet.Lookup.
Implements a virtual method to retrieve field values from a record that matches specified search values.
This function:
Checks whether the dataset is unidirectional, and if so, raises an EDatabaseError exception.
Returns a Variant with the value false, indicating that a matching record was not found.
Descendant classes that are not unidirectional override this method so that it locates the record where the fields identified by the comma-delimited string KeyFields have the values specified by the Variant or Variant array KeyValues. In classes that implement Lookup, it returns a Variant or Variant array that contains the value or values of the fields specified by the comma-delimited string ResultFields on the specified record.