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CurValue

property CurValue: Variant read;

Example​

function CurrentServerValue(const Data: TvxClientDataSet): Variant;
begin
  Result := Data.FieldByName('Status').CurValue;
end;

Usage​

CurValue reads the client dataset's current reconciled state value for a stored field, distinguishing an unavailable or unchanged value from explicit database Null.

  • Test VarIsEmpty/VarIsClear for Unassigned separately from VarIsNull.
  • Use ordinary Value for the active pending record; use this member only in change-log/reconciliation logic that understands client-dataset state buffers.
  • Do not assume it performs a new database query or reflects a concurrent server change.

Additional Technical Info​

CurValue reads a field using dataset state dsCurValue. It is a client-dataset change/reconciliation view, not a synonym for the current record's ordinary Value.

Source-backed behaviour​

TField.GetCurValue delegates to DataSet.GetStateFieldValue(dsCurValue, Self). The base dataset temporarily changes its internal state, calls the concrete field's AsVariant, then restores the previous state; non-stored field kinds return Null. TCustomClientDataSet adds DSBase blank-state handling: BLANK_NOTCHANGED becomes Unassigned, BLANK_NULL becomes Null, and only a present value is converted through the field.

When no current-value buffer is available, the client override also yields Unassigned. Therefore callers must not interpret every non-value as database null. The temporary state change is internal and restored with finally, but descendant getters and conversion exceptions can still propagate.

Official RTL references​

Created 2026-07-15