SPRegionalSettings.Time24 Property
Gets or sets a Boolean value that specifies whether to use a 24-hour time format in representing the hours of the day.
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: Yes
Available in SharePoint Online
Property Value
Type: System.Booleantrue if the hours of the day are represented in 24-hour format; otherwise, false to display in 12 hour AM/PM format.