How to bind SelectionStart Property of Text Box?

Question

I use this:

but it always shows 0.<

Answer 1

This could be an alternate solution:

View:

ViewModel:

    #region TextBoxSelectionChangedCommand
    RelayCommand _TextBoxSelectionChangedCommand = null;
    public ICommand TextBoxSelectionChangedCommand {
        get {
            if (_TextBoxSelectionChangedCommand == null) {
                _TextBoxSelectionChangedCommand = new RelayCommand((r) => TextBoxSelectionChanged(r), (r) => true);
            }

            return _TextBoxSelectionChangedCommand;
        }
    }

    protected virtual void TextBoxSelectionChanged(RoutedEventArgs _args) {
        YourCursorPositionVariable = (_args.OriginalSource as System.Windows.Controls.TextBox).SelectionStart;
    }
    #endregion

I agree you has to cast TextBox component type in ViewModel and it's a kind of coupling, but create a custom component will impose to bind on a specific property as well.