Author: Tomas Rutkauskas

Keep a dataset in dsInsert/dsEdit mode after validation fails

Answer:

If you want to keep a dataset in dsInsert/dsEdit mode after a validation fails, but 
do not want to loose your input, use Abort in the BeforePost() event.

(If you would use Dataset.Cancel, you'd loose the input and return to browse mode.) 
1   
2   procedure TForm1.Table1BeforePost(DataSet: TDataSet);
3   begin
4     if Table1ID.Value <= 0 then
5     begin
6       // the data is invalid!!
7       Showmessage('Error! Invalid value!');
8       Abort
9     end
10    else
11      Table1.Post;
12  end;