I found this routine which copies the current record of the currently selected record. This is useful e.g. to keep a temporary record for display in a form.
{************************************************
// procedure AppendCurrent
//
// Written By: Steve Zimmelman
// 6/4/96
//
// Version: Delphi 2.0
//
// Will append an exact copy of the current
// record of the dataset that is passed into
// the procedure and will return the dataset
// in edit state with the record pointer on
// the currently appended record.
************************************************}
procedure AppendCurrent(Dataset:Tdataset);
var
aField : Variant;
i : Integer;
begin
// Create a variant Array
aField := VarArrayCreate(
[0,DataSet.Fieldcount-1],
VarVariant);
// read values into the array
for i := 0 to (DataSet.Fieldcount-1) do
begin
aField[i] := DataSet.fields[i].Value ;
end;
DataSet.Append ;
// Put array values into new the record
for i := 0 to (DataSet.Fieldcount-1) do
begin
DataSet.fields[i].Value := aField[i] ;
end;
end;