when if condition fails i want to clear all records from the form
please give me any example
No, it's you who should give an example of what you're trying to achieve.
For example, what do you mean by "clear all records from the form"? Deleting all data from all tables used in the form? Persistent or temporary? Which from? Or deleting all data returned by the current query? Or keeping all data intact and just not showing it in the form?
When do you interpret the condition?
You see, if you don't explain your requirement, there is little we can do for you...