>Hi,
> I would like to know that, how does validation data being done, when user press save button or lost locus/valid for each controls??
>
>Thank you

You may get various opinions on this. Generally, if possible I validate at the field level so the user has a chance to immediately change invalid data for that control. However, others feel this is not very efficient for heads down data entry and prefer to validate at the Save. Also, sometimes it's necessary to validate a field or fields against other fields or even external criteria that might require having data in all or most fields before validation can be done. In this case I would probably wait until the Save takes place. A proper validation scheme is probably goin to depend on the specific scenario you have in any given instance.

IMO it is generally good to learn to analyze the current requirements and not be forced into the "always do it this way" mode.

Bill