--- a/appobject.py	Thu May 28 18:28:05 2009 +0200
+++ b/appobject.py	Thu May 28 18:28:29 2009 +0200
@@ -301,6 +301,35 @@
             return self.req.property_value('ui.float-format') % num
         return u''
 
+    def parse_datetime(self, value, etype='Datetime'):
+        """get a datetime or time from a string (according to etype)
+        Datetime formatted as Date are accepted
+        """
+        assert etype in ('Datetime', 'Date', 'Time'), etype
+        # XXX raise proper validation error
+        if etype == 'Datetime':
+            format = self.req.property_value('ui.datetime-format')
+            try:
+                return todatetime(strptime(value, format))
+            except:
+                pass
+        elif etype == 'Time':
+            format = self.req.property_value('ui.time-format')
+            try:
+                # (adim) I can't find a way to parse a Time with a custom format
+                date = strptime(value, format) # this returns a DateTime
+                return datetime.time(date.hour, date.minute, date.second)
+            except:
+                raise ValueError('can\'t parse %r (expected %s)' % (value, format))
+        try:
+            format = self.req.property_value('ui.date-format')
+            dt = strptime(value, format)
+            if etype == 'Datetime':
+                return todatetime(dt)
+            return todate(dt)
+        except:
+            raise ValueError('can\'t parse %r (expected %s)' % (value, format))
+
     # security related methods ################################################
 
     def ensure_ro_rql(self, rql):