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FindField

function FindField(const FieldName: string): TField;

Example​

procedure ReadOptional(const Data: TvxClientDataSet; var Value: string);
var
  Field: TField;
begin
  Field := Data.FindField('OptionalCode');
  if Field = nil then
    Value := ''
  else
    Value := Field.AsString;
end;

Usage​

FindField returns the matching field reference or nil when the named field is not present.

  • Test against nil before dereferencing.
  • Use FieldByName when a missing field must raise.
  • Do not cache across dataset close/reopen paths that recreate dynamic fields.

Additional Technical Info​

FindField is declared by hidden ancestor TDataSet and is normally used through a visible descendant such as TvxClientDataSet. It is the non-raising field lookup.

Source-backed behaviour​

The method searches primary FFields, then object-view fields when enabled, then aggregate fields. The primary collection uses lowercased dictionary keys, giving case-insensitive matching. No field definition is created and no data is fetched solely because the name is missing.

A non-nil result is a live TField component whose Value represents the dataset's current record and state.

GetFieldNames can populate a list of available names. FieldCount counts current field components.

Official RTL references​

Created 2026-07-15