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DBCons

property DBCons[Index: Integer]: TvxDBLink read;

Example​

procedure CheckConfiguredLinks(const Data: TvxDBDef);
var
  I: Integer;
begin
  for I := 0 to Data.DBConCount - 1 do
    if Data.DBCons[I].DBCon = nil then
      raise Exception.Create('Database connection ' + IntToStr(I) + ' did not load');
end;

Usage​

DBCons returns a zero-based database-link object by its current configuration-list index without performing bounds checking.

  • Re-read DBConCount and stay within 0..count-1 in the same operation.
  • Check DBCons[I] and its DBCon result before use; do not confuse the link with the connection.
  • Do not assume index zero is semantically primary unless the module configuration defines it that way.

Additional Technical Info​

DBCons[index] returns one TvxDBLink from the data definition's current ordered list. The returned object describes a link to a connection; it is not itself the TvxDBCon.

Source-backed behaviour​

The getter casts FDBCons[Index] directly. Indexing is zero-based and there is no local range guard. Negative indexes or values at/above DBConCount raise through the underlying list.

Reading the link is cheap, but subsequently reading its DBCon property may create a connection object, load its module from configuration and log a failure before returning nil. Link order is configuration order and is also the order used by the group transaction methods.

The list and its objects are owned by the data definition. Module transfer/loading can free and rebuild them, so retained references can become invalid.

Created 2026-07-15