I am using C # .NET and I have a windows form with DateTimePicker.
My question is: how can I display hours and minutes (to change the user) along with the year, month and day?
Check the CustomFormat property: http://msdn.microsoft.com/en-us/library/system.windows.forms.datetimepicker.customformat.aspx
It allows you to set the format, whatever you want. In addition to apply it, you need to set DatetimePicker.Format to Custom.
EDIT: if you provided a better idea / example of the format you want to display, I can help with the actual format string.
Set the Format property to DateTimePickerFormat.Custom and set the CustomFormat property to a format that includes time.
Format
DateTimePickerFormat.Custom
CustomFormat
See all DateTimePicker properties here:
http://msdn.microsoft.com/en-us/library/system.windows.forms.datetimepicker_properties.aspx
The Format property allows you to set the format string, including hours, minutes, seconds.
Edit:
Here are the predefined formats:
http://msdn.microsoft.com/en-us/library/system.windows.forms.datetimepickerformat.aspx
As with other posters, you can set your own format in the CustomFormat property.