Problem:
There are a TextBox and a Button on the form,the Button is set to the CancelButton of Form. TextBox.CancelValidation
property is set to true, while Button.CancelValidation is set to false. When clicked on Button the validation is not performed and form closes successfully but pressing ESC key does not close the Form.
Clicking on the button [...]

Most of the time Update(object) method is enough to update record using NHibernate. Instead you can use update query to update records, sometimes you might have special cases to write your own update query to update records on the database. Here is the simple sample how to write update query with NHibernate.

using(ISession session [...]