Error Unknown Type : 14

mseehuber

In the TFrxDBDataSet.DoGetValue procedure some kind of fields raise this error.

They are definitly in the Resultset. Others are displayed without any Problems.

There is an opened TADODataSet and this is linked to an TFrxDBDataSet.

Any idea whats wrong ?

EDIT:

Via the frxReport.GetValue function the values are shown without any Problem.
VarName = <TADODataset-Name>:<FieldName>.

mseehuber

No Answer is also an answer.

Maybe is this an big Bug or does anyone use an TBetterAODDataset or TADODataset resultset with an TFrxDBDataSet without any Problems.

mseehuber

To check, if this is an bug, i used an kbmemtable and copied all record into it.

And, which surprise, with this memory table the report works. So there is definitly an bug with TADODatasets and retrieving values from fields.

mseehuber

Problem located :

Unit : frxClass.pas

function TfrxReport.DoGetValue(const Expr: String; var Value: Variant): Boolean;
...
GetDataSetAndField(Expr, ds, fld);
if (ds <> nil) and (fld <> '') then
begin
Value := ds.Value[fld];
if FEngineOptions.ConvertNulls and (Value = Null) then
...
...


if FEngineOptions.ConvertNulls and (Value = Null) then
raises sometimes in the ( Value = Null ) condition an Exception.

On changing this to
if FEngineOptions.ConvertNulls and ( VarType( Value ) = 0 ) then

all workes fine, all all data are shown.

DiGi

Value = Null is bad, should be

VarIsNull(Value)