how to get the type of datacontext of a listbox at runtime in wpf

You can use the GetType method to find the Type of any entity. You need to be careful when trying to find the Type from a DataContext though, because unless the DataContext for the ListBox is specifically set, it will return the ViewModel or Window as the Type. For Example, if I have these classes:-

public class Person
    {
        public string Name { get; set; }
        public int Age { get; set; }
    }
    public class People : ObservableCollection<Person>
    {
        public People()
        {
            for (int i = 0; i < 5; i++)
            {
                Person person = new Person() { Age = i + 20, Name = "Person " + i.ToString() };
                this.Add(person);
            }
        }
    }

and I have a Property in my code behind like so:-

public People peoples;
        public People Peoples
        {
            get
            {
                return peoples;
            }
            set
            {
                peoples = value;
                NotifyPropertyChanged("Peoples");
            }
        }

which I set as the ItemsSource of my ListBox

Type contextType = lb.DataContext.GetType();

gives me MainWindow(the name of my window)

Type contextType = lb.ItemsSource.GetType();

gives me People as the Type and

Type contextType = lb.Items[0].GetType();

gives me Person as the Type.