Check if an adoquery field exists

stol

Hello, I made an adoquery in access whose fields change each time I call it from fast report. How can I check if it's fields exist when I use it in fast report. I used this code
if <ADOQuery2.fieldbyname('aircrewstatus') = null then showmessage('don't exist'); but it does not work and this message appears ( Can't find field "aircrewstatus"). Can anyone help me?? Thanks.

Anu de Deus

try using the ADOQuery2.GetFieldNames procedure and analise the results.

They are part of TDataset and implemented in the frx editor, should be fine, take a look at the Classes tab in the right side of the frx editor, plenty of good stuff there.

stol

Anu de Deus wrote: »

try using the ADOQuery2.GetFieldNames procedure and analise the results.

They are part of TDataset and implemented in the frx editor, should be fine, take a look at the Classes tab in the right side of the frx editor, plenty of good stuff there.

stol

I tried that showmessage(adoquery2.GetFieldNames); but didn't work. The message Undeclared Idendifier : 'GetFieldNames' appeared. Am I doing something wrong?

Anu de Deus

yes, you are.
As I said, look at the tab, there is the function declaration there, with its required parameters

stol

Sorry but I can't find the solution. I found the procedure GetFieldNames(List: TStrings) but I don't know how to use it. What should I write in the parenthesis? Can you send me an example? Thanks.

gpi

var List: TStringList;           
begin
     ADOQuery1.Open;              
     List := TStringList.Create;                                                                                 
     ADOQuery1.GetFieldList(List);
     if List.IndexOf('Company') <> -1 then ShowMessage('Company field exists');
     List.Free;                           
end.

stol

It works!!! Thank you very much.