按鈕的Click事件
if not (DBGrid1.DataSource.DataSet.State in [dsEdit, dsInsert]) then
DBGrid1.DataSource.DataSet.Edit;
DBGrid1.DataSource.DataSet.FieldByName('字段名').AsString :=
DBGrid1.DataSource.DataSet.FieldByName('字段名').AsString + TButton(Sender).Caption;