What is the proper way to use static variable in OOP?

I'm working on Employee Management System. Each employee belong to one department, when employee logged in to system I store UserId and DepartmentId in my class as below

internal static class MyStaticData
{
    internal static Guid UserId { get; set; }
    internal static Guid DepartmentId { get; set; }
}

When user go to create leave application page and hit save button, I need to send both UserId and DepartmentId to store in database, so what is the proper way to send UserId and DepartmentId to this page between

// Create instance property inside the class and assign it when create new object.
public class LeavePage
{
    public Guid UserId { get; set; }
    public Guid DepartmentId { get; set; }
}

var leavePage = new LeavePage { UserId = MyStaticData.UserId, DepartmentId = MyStaticData.DepartmentId };

or

// Don't have instance property inside the class but use MyStaticData directly
public class LeavePage
{
    public void Save()
    {
        Db.Save(data, ..., My开发者_JAVA百科SataicData.UserId, MyStaticData.DepartmentId);
    }
}

I'm not sure which one is better (less coupling) or does it has better way to do this?

You might want to try using a static instance of some more general class - something like this:

public class User
{
    public Guid Id { get; set; }
    public Guid DepartmentId { get; set; }
}

public static class SessionContext
{
    public static User CurrentUser { get; set; }
}

Then use SessionContext.CurrentUser when saving.

Of course, in this case using a static class is probably inappropriate, and you should look into a session-specific instance.

If there is no need to include instances of your values in your class, do not do it.