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RecordPosition

property RecordPosition: Cardinal read write

Example​

procedure ScriptEvent(var Value: variant);
var
  SavedPosition: Cardinal;
begin
  SavedPosition := DATA1.RecordPosition;
  // Consume immediately while data, filter and index remain unchanged.
  DATA1.RecordPosition := SavedPosition;
  Value := DATA1.RecordPosition;
end;

Usage​

RecordPosition gets or sets the current client-dataset RecNo through a range-checked unsigned Cardinal function.

Usage notes

Use only for immediate temporary restoration under unchanged packet/index/filter state. Prefer a unique business-key Find for durable repositioning.

Setter

The Cardinal is passed to a signed Integer RecNo setter. With the product's range checking, values above MaxInt raise ERangeError before RecNo/cursor work; never use them. If the in-range target differs, RecNo enters browse mode, can post a pending edit, fires BeforeScroll, calls MoveToSeqNo, recentres/resynchronises and fires AfterScroll.

An invalid/out-of-range position raises. A failure after browse/post or BeforeScroll can still have side effects even if no final reposition occurs.

Additional Technical Info​

RecordPosition is a Velox name/type wrapper over inherited client-dataset RecNo. Reading returns RecNo converted from signed Integer to Cardinal; writing converts the Cardinal back and assigns RecNo.

The example round-trips immediately under unchanged state. It is source-reviewed and was not executed by the documentation workflow.

In normal active browse state, client-dataset RecNo is a 1-based sequence position. It is not a zero-based offset, bookmark, database key or durable row identity. IndexFieldNames, filters/ranges, inserts/deletes, loads and data refresh can change which record a number identifies.

Getter

Native RecNo checks that the dataset is active and reads the active record buffer's internal sequence number. During dsInternalCalc it returns -1. Velox is compiled with Delphi range checking enabled, so assigning that sentinel to the Cardinal result raises ERangeError; it does not wrap to 4294967295. Inactive access raises a dataset error first.

Performance and concurrency

Positioning cost depends on client-dataset cursor/index internals and resync. The position and cursor are mutable unsynchronised state.

External references

Created 2026-07-15