public class Person
{
    public int Id { get; set; }
    public string LastName { get; set; }
    public string FirstName { get; set; }
    public DateTime DOB { get; set; } 

    public Person()
    {
        Id = 0;
        LastName = String.Empty;
        FirstName = String.Empty;
        DOB = DateTime.Now;
    }
}


private void button1_Click(object sender, EventArgs e)
{
    var v = new Person(){
                    LastName = "LLLLL";
                    FirstName = "FFFFF";
                    DOB = DateTime.Now;
                };

    _dbContext.Add(v);



    // now let's say that the user changes the v.LastName to ...
    v.LastName = "QQQQQQQQQQQQQQQQQQQQQQQQQQ";

    /* now I would expect _dbContext to be already aware of changes 
       made to the v.LastName property or at least to have passed the initial
       values of the v entity to the OriginalValues of the added entry
       and EFCore to providing me with a method to informing me, 
       whenever I asked so,
       if some property values in the entity, being tracked, have been changed!!
    */

   //so whenever I type
   var changesMadeSoFar = HelloLovelyEFCore_DoWeHaveAnyChangesToThePropertiesOfThisLovelyEntryMadeSoFar(EntityEntry v);

  // Unfortunatelly I can't find a way to be inormed of any changes in the properties
  // of the entry being tracked!! Unless I am missing something... (which is very possible)

  //  Even the following fails to provide me information of property changes
      made to a NEWLY created entity NOT a loaded for the DB ones.....

    EntityEntry<TFlatVisit> entry = _dbContext.Entry(v);
    entry.DetectChanges();
    var modified = entry.Members.Where(m => m.IsModified).ToList();
    var modified2 = entry.Properties.Where(m => m.CurrentValue != m.OriginalValue).ToList();
    var modified3 = entry.Properties.Where(m => m.CurrentValue == m.OriginalValue).ToList();

    var modified4 = entry.Properties
        .Where(prop => prop.IsModified)
        .Select(prop => new
        {
            Property = prop.Metadata,
            Value = prop.CurrentValue,
            Name = prop.Metadata.Name,
            PrevValue = prop.OriginalValue
        }).ToList();

 
    if (_dbContext.ChangeTracker.HasChanges())
    {
        _dbContext.ChangeTracker.DetectChanges();
        Debug.WriteLine(_dbContext.ChangeTracker.DebugView.LongView);
    }// the latter results into _dbContext has changed and the state of entry v is set to Added (we all know that)

}

PS：我不是在询问条目是否已更改！！条目状态更改为Added。我们都知道这一点！！我是在特别询问一种方法来了解条目的某些或任何属性是否已更改。而且我希望通过EFCore获取此信息！！而不是通过INotifyPropertyChanged之类的东西。希望已经向您说明了我的目的...
PS2：我不是在询问对使用_dbContext从数据库加载的实体所做的更改。我特别询问对新创建条目的属性所做的更改的信息。
看起来_dbContext和EFCore没有将新创建条目的属性的初始值传递给OriginalValues！！我不知道为什么会这样？！？将新创建条目的OriginalValues设置为添加到_dbContext的对象的初始值难道不合理吗？！？因此，让我们有机会通过比较原始值和当前值来检测属性的更改？！？！
谢谢你的时间