time.cs

功能：基于windows mobile 的地图查看器。使用vs2005开发

using System;
using System.Runtime.InteropServices;

namespace PInvokeLibrary
{
	/// <summary>
	/// Allows the user to get/set the system time.
	/// </summary>
	public class Time
	{
		/// <summary>
		/// This structure represents a date and time using individual members for
		/// the month, day, year, weekday, hour, minute, second, and millisecond. 
		/// </summary>
		public struct SYSTEMTIME 
		{
			/// <summary>
			/// Specifies the current year.
			/// </summary>
			public ushort wYear; 
			/// <summary>
			/// Specifies the current month; January = 1, February = 2, and so on.
			/// </summary>
			public ushort wMonth; 
			/// <summary>
			/// Specifies the current day of the week; Sunday = 0, Monday = 1, and so on.
			/// </summary>
			public ushort wDayOfWeek; 
			/// <summary>
			/// Specifies the current day of the month.
			/// </summary>
			public ushort wDay; 
			/// <summary>
			/// Specifies the current hour.
			/// </summary>
			public ushort wHour;
			/// <summary>
			/// Specifies the current minute.
			/// </summary>
			public ushort wMinute;
			/// <summary>
			/// Specifies the current second.
			/// </summary>
			public ushort wSecond;
			/// <summary>
			/// Specifies the current millisecond.
			/// </summary>
			public ushort wMilliseconds;
		}

		/// <summary>
		/// This function retrieves the current system date and time. The system time
		/// is expressed in Coordinated Universal Time (UTC).
		/// </summary>
		/// <param name="lpSystemTime">[out] Pointer to a SYSTEMTIME structure to
		/// receive the current system date and time.</param>
		[DllImport("coredll.dll")]
		public extern static void GetSystemTime(ref SYSTEMTIME lpSystemTime);

		/// <summary>
		/// This function sets the current system time and date. The system time is
		/// expressed in Coordinated Universal Time (UTC).
		/// </summary>
		/// <param name="lpSystemTime">[in] Pointer to a SYSTEMTIME structure that
		/// contains the current system date and time.</param>
		/// <returns></returns>
		[DllImport("coredll.dll")]
		public extern static uint SetSystemTime(ref SYSTEMTIME lpSystemTime);

		/// <summary>
		/// Run a test of the Time class.
		/// </summary>
		/// <param name="showLine">Delegate called to show debug information</param>
		public static void TestProc(MainTest.DisplayLineDelegate showLine)
		{
			DateTime dt = DateTime.UtcNow.ToLocalTime();
			showLine(String.Format("Current Time: {0}:{1:00}:{2:00} {3}", dt.Hour > 12 ? dt.Hour - 12 : dt.Hour, dt.Minute, dt.Second, dt.Hour > 12 ? "PM" : "AM"));

			SYSTEMTIME st = new SYSTEMTIME();

			GetSystemTime(ref st);

			showLine("Adding 1 hour...");
			st.wHour = (ushort)(st.wHour + 1 % 24);
			if (SetSystemTime(ref st) == 0)
				showLine("FAILURE: SetSystemTime failed");

			dt = DateTime.UtcNow.ToLocalTime();
			showLine(String.Format("Current Time: {0}:{1:00}:{2:00} {3}", dt.Hour > 12 ? dt.Hour - 12 : dt.Hour, dt.Minute, dt.Second, dt.Hour > 12 ? "PM" : "AM"));

			showLine("Setting time back...");
			st.wHour = (ushort)(st.wHour - 1 % 24);
			if (SetSystemTime(ref st) == 0)
				showLine("FAILURE: SetSystemTime failed"); 

			dt = DateTime.UtcNow.ToLocalTime();
			showLine(String.Format("Current Time: {0}:{1:00}:{2:00} {3}", dt.Hour > 12 ? dt.Hour - 12 : dt.Hour, dt.Minute, dt.Second, dt.Hour > 12 ? "PM" : "AM"));
		}
	}
}