CODEWITHSUNDEEP
c#.netvb.net
user62958
user62958

Reputation: 4929

How to update the system's date and/or time using .NET

I am trying to update my system time using the following:

[StructLayout(LayoutKind.Sequential)] 
private 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;
}

[DllImport("kernel32.dll", EntryPoint = "GetSystemTime", SetLastError = true)]
private extern static void Win32GetSystemTime(ref SYSTEMTIME lpSystemTime);

[DllImport("kernel32.dll", EntryPoint = "SetSystemTime", SetLastError = true)]
private extern static bool Win32SetSystemTime(ref SYSTEMTIME lpSystemTime);

public void SetTime()
{
    TimeSystem correctTime = new TimeSystem();
    DateTime sysTime = correctTime.GetSystemTime();
    // Call the native GetSystemTime method
    // with the defined structure.
    SYSTEMTIME systime = new SYSTEMTIME();
    Win32GetSystemTime(ref systime);

    // Set the system clock ahead one hour. 
    systime.wYear = (ushort)sysTime.Year;
    systime.wMonth = (ushort)sysTime.Month;
    systime.wDayOfWeek = (ushort)sysTime.DayOfWeek;
    systime.wDay = (ushort)sysTime.Day;
    systime.wHour = (ushort)sysTime.Hour;
    systime.wMinute = (ushort)sysTime.Minute;
    systime.wSecond = (ushort)sysTime.Second;
    systime.wMilliseconds = (ushort)sysTime.Millisecond;

    Win32SetSystemTime(ref systime);
}

When I debug everything looks good and all the values are correct but when it calles the Win32SetSystemTime(ref systime) th actual time of system(display time) doesn't change and stays the same. The strange part is that when I call the Win32GetSystemTime(ref systime) it gives me the new updated time. Can someone give me some help on this?

Upvotes: 10

Views: 16064

Answers (7)

Jaans
Jaans

Reputation: 4638

No need for P/Invoke - there is a simpler way (but not well known) available from the Microsoft.VisualBasic assembly. If you are in C#, just remember to add a reference to it.

You can use the Microsoft.VisualBasic.DateAndTime class to get and change the Date or Time. The properties Today and TimeOfDay have setters that will make the changes to the date or time.

You still need the relevant privileges - refer to the MSDN documentation link below.

Here's an arbitrary example to change the time:

public static void SetTimeToPast()
{
    Microsoft.VisualBasic.DateAndTime.TimeOfDay = DateTime.Now.AddMinutes( -2 );
}

Reference on MSDN: http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.dateandtime(v=vs.110).aspx

Upvotes: 3

user2118273
user2118273

Reputation: 1

You have just a privileges problem, when I run that program without privileges, it does'nt changes the date, but if i do right click on the program, and click on run as administrator, it works!

Upvotes: 0

erfan
erfan

Reputation: 11

 [DllImport("Kernel32.dll")]
 public static extern bool SetLocalTime(ref StractData.Datetime.SYSTEMTIME Time);

Upvotes: 1

mtaskopru
mtaskopru

Reputation: 139


TimeSpan diffLocalTime = DateTime.Now - DateTime.UtcNow; 
SystemTime systemTime = new SystemTime(); 
systemTime.Second = ... 
systemTime.Minute =.... 
systemTime.Hour -= (ushort)(diffLocalTime.Hours + 1); // 00:59:59 I rounded as 1 hour 
bool result = SetSystemTime(ref systemTime);

This using It's working correctly for local time zone.

Upvotes: 2

Lei
Lei

Reputation: 699

The problem is about UTC time and local time. See this link: http://www.codeproject.com/Messages/2998246/problem-with-SetSystemTime-fucntion-of-Kernel32-dl.aspx

Hope this maybe helpful for you.

Upvotes: 1

JaredPar
JaredPar

Reputation: 755397

Part of your problem is that you have a couple of incorrect PInvoke signatures. Most notable SetSystemTime should have a non-void return value. Here is the correct signature

    /// Return Type: BOOL->int
    ///lpSystemTime: SYSTEMTIME*
    [System.Runtime.InteropServices.DllImportAttribute("kernel32.dll", EntryPoint="SetSystemTime")]
    [return: System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.Bool)]
public static extern  bool SetSystemTime([InAttribute()] ref SYSTEMTIME lpSystemTime) ;

My suspicion is that the lock of a return value messed up the stack and the SetSystemTime function essentially ended up with bad data.

Upvotes: 7

David Morton
David Morton

Reputation: 16505

According to the code you have right there, you're not incrementing the hour. It looks like you're setting your system time to the exact same time as it was when you called Win32GetSystemTime.

Try:

systime.wHour = (ushort)(sysTime.Hour + 1);

Upvotes: 4

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