using System;

using System.Runtime.InteropServices;

using System.Windows.Forms;

namespace Demo

{

    public partial class 设置系统时间 : Form

    {

        public 设置系统时间()

        {

            InitializeComponent();

        }

        private void btnSetting_Click(object sender, EventArgs e)

        {

            //取得当前系统时间

            DateTime t = DateTime.Now;

            //在当前时间上加上一周

            t = t.AddDays(7);

            t = DateTime.Parse(this.dtpTime.Text);

            //转换System.DateTime到SYSTEMTIME

            SYSTEMTIME st = new SYSTEMTIME();

            st.FromDateTime(t);

            //调用Win32 API设置系统时间

            Win32API.SetLocalTime(ref st);

            //显示当前时间

           // MessageBox.Show(DateTime.Now.ToString());

        }

    }

    /// <summary>

    ///

    /// </summary>

    public struct SYSTEMTIME

    {

        public ushort wYear;

        public ushort wMonth;

        public ushort wDayOfWeek;

        public ushort wDay;

        public ushort wHour;

        public ushort wMinute;

        public ushort wSecond;

        public ushort wMilliseconds;

        /// <summary>

        /// 从System.DateTime转换。

        /// </summary>

        /// <param name="time">System.DateTime类型的时间。</param>

        public void FromDateTime(DateTime time)

        {

            wYear = (ushort)time.Year;

            wMonth = (ushort)time.Month;

            wDayOfWeek = (ushort)time.DayOfWeek;

            wDay = (ushort)time.Day;

            wHour = (ushort)time.Hour;

            wMinute = (ushort)time.Minute;

            wSecond = (ushort)time.Second;

            wMilliseconds = (ushort)time.Millisecond;

        }

        /// <summary>

        /// 转换为System.DateTime类型。

        /// </summary>

        /// <returns></returns>

        public DateTime ToDateTime()

        {

            return new DateTime(wYear, wMonth, wDay, wHour, wMinute, wSecond, wMilliseconds);

        }

        /// <summary>

        /// 静态方法。转换为System.DateTime类型。

        /// </summary>

        /// <param name="time">SYSTEMTIME类型的时间。</param>

        /// <returns></returns>

        public static DateTime ToDateTime(SYSTEMTIME time)

        {

            return time.ToDateTime();

        }

    }

    public class Win32API

    {

        [DllImport("Kernel32.dll")]

        public static extern bool SetLocalTime(ref SYSTEMTIME Time);

        [DllImport("Kernel32.dll")]

        public static extern void GetLocalTime(ref SYSTEMTIME Time);

    }

}