binding for the text control - WPF - C#

Question

Hello,

How I can make a binding for the text control?
I use as DataContext ViewModel.

  public class ViewModel : INotifyPropertyChanged  
    {  
        private CollectionViewSource cvs1 = new CollectionViewSource();  
        private ObservableCollection<Order> ColOrders;  
        public ICollectionView View1 { get => cvs1.View; }  
        private CollectionViewSource cvs2 = new CollectionViewSource();  
        private ObservableCollection<Material> col2;  
        public ICollectionView View2 { get => cvs2.View; }  
        public ICommand Cmd { get => new RelayCommand(CmdExec, CanCmdExec); }  
  
        //public ViewModel()  
        //{  
        //    CurrentUIData = new UserData();  
        //}  
        public string CurrentOrderNo { get; set; }  

<Window.Resources>  
    <local:ViewModel x:Key="vm"/>  

Answer 1

Where is your problem?

Hi Peter, big problem!

        private void CmdExec(object obj)
        {
            switch (obj.ToString())
            { 
                case "AddOrder":
                    //nt newOrderNumber = (this.ColOrders.Count > 0) ? this.ColOrders.Max((ord) => ord.OrderNumber) + 1 : 1;
                    var o = new Order() { OrderNumber = "TEST1" };
                    this.ColOrders.Add(o);
                    this.View1.MoveCurrentTo(o);

We have the TextBox Order. The operator insert this number now as string.
How can I access the UI controls directly from ViewModel?
And I need like a Init() function. How can I do that?
I want not to press first Load()

        <TextBox Grid.Row="0" Grid.Column="0" Text="{Binding CurrentOrderNo}"  HorizontalAlignment="Left" 

Works not.

The goal:
var o = new Order() { OrderNumber = textBox der Usereingabe };

Can you help me again, please?

new ObservableCollection<Order>();
Init to create a new list.

How I can call a Init() function for ViewModel ?