One of the standards in our databases is to store dates as 8-digit integer values in the format of yyyymmdd. This requires us to occasionally convert values from date fields into this format. We can do this in the ArcMap Field Calculator using this arcpy function: def datetodouble(inNum): splitList = str(inNum).split("/") return splitList  +("0"+ splitList )[-2:] +("0"+ splitList )[-2:]
While working on a VB.Net form to query a database that includes an optional date range query, I decided I wanted to display a datetimepicker with a blank value by default and then, if the user sets a date show the date. By default, a datetimepicker can not have a Null date, so I went a’Googling and found this post, .NET Reference: Setting the DateTimePicker to a Blank Value,that had exactly the technique I wanted.