A Calendar control displays a standard month calendar where the user can select a date.
To retrieve the date being currently shown in a Calendar control, call wb_get_value(). The date is retrieved as a standard Unix timestamp that can be entered directly into PHP functions like date(), getdate() and strftime().
Conversely, wb_set_value() can be used to set the current date of a Calendar control. the date must be a standard Unix timestamp such as those values returned from PHP functions mktime(), strtotime() and time().