>I have an idea to make user can modify it's report, but the application should still have control that won't let user to delete the report fields,...
>just to change like the position of report fields, change the font and color and user may add report field
>
>And of course it's all performed in designed mode like We designed it,....
>
>Is there any suggestion,..??

Erik's right, if they can move/edit it, they can delete it. You may be able to define an ON KEY LABEL for the Delete key to stop it, but they could still delete the field through the menu. Wait, you could also redfine the Cut command (Ctrl+X) from the edit menu, because that should be the only other way to remove a field.

I Just tried this and you can stop the Keyboard of the Cut command, but the Menu will still cut and remove the field. Anyways, 2 out of 3 ain't bad, maybe?

PUSH KEY
ON KEY LABEL DEL *
ON KEY LABEL Ctrl+X *
MODI REPORT xxxx
POP KEY