События и команды в WPF

private void FindOnExecute(object sender, RoutedEventArgs e)
        {
            CreateDialog();
        }
    
        private void FindNextOnExecute(object sender, RoutedEventArgs e)
        {
            if (_dlg == null)
                CreateDialog();
            else
                FindNextExec();
        }
    
        private void ReplaceOnExecute(object sender, RoutedEventArgs e)
        {
            if (_dlg == null)
            {
                CreateDialog();
                _dlg.ShowReplace = true;
            }
            else if (_dlg.ShowReplace == false)
                _dlg.ShowReplace = true;
            else
                ReplaceExec();
        }
    
        private void GoToOnExecute(object sender, RoutedEventArgs e)
        {
        }

<ToolBar Header="Find:">
                <TextBox Width="100" />
                <Button Name="btnFind" Click="FindOnExecute" Width="23" Content="{StaticResource iconFind}" />
            </ToolBar>

<Window x:Class="Notepad1.GoToDialog"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    SizeToContent="WidthAndHeight"
    WindowStartupLocation="CenterOwner"
    ShowInTaskbar="false"
    Title="Go To Line"
    ResizeMode="NoResize"
    Activated="OnActivated"
    >
    <StackPanel 
        Background="{StaticResource DialogBackgroundBrush}"
        >
        <StackPanel
            Orientation="Vertical"
            Margin="5"            
            >
            <Label
                Name="_rangeNumber"
                Margin="0 0 8 3"
                VerticalAlignment="Bottom"
                Content="_Line number" />
            <TextBox
                Name="_lineNumberTextBox"
                TabIndex="0"
                MinWidth="220"
                Margin="5,0" />
        </StackPanel>
    
        <StackPanel
            Orientation="Horizontal"
            Margin="5,0,5,5" HorizontalAlignment="Right">
            <Button
                Click="OkClicked"
                IsDefault="true"
                MinWidth="75"
                MinHeight="23"
                Content="OK" />
            <Button
                Click="CancelClicked"
                IsCancel="true"
                Margin="15 0 5 0"
                MinWidth="75"
                MinHeight="23"
                Content="Cancel" />
        </StackPanel>
    </StackPanel>
</Window>

GotoErrorDialogTitle=Go To Line Error
GotoErrorMsgFormat=Текстовое поле должно\nсодержать целое число
GotoErrorMsgEmpty=Введите число в текстовое поле
GotoErrorMsgRange=Выход за границы диапазона

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
    
// Дополнительные подключения пространств имен
using System.Resources;
using System.Reflection;
    
namespace Notepad1
{
    public partial class GoToDialog : Window
    {
        public GoToDialog()
        {
            InitializeComponent();
    
            // Сохраняем первое значение Label
            _rangeOrigin = _rangeNumber.Content.ToString();
        }
    
        // Объявляем событие для прослушивания в основном окне
        public event EventHandler GotoActivate;
    
        // Закрытые поля класса
        int _lineNumber = 0;
        int _maxLineNumber;
        ResourceManager res =
            new ResourceManager("Notepad1.StringTable", 
                Assembly.GetExecutingAssembly());
        String _rangeOrigin;
    
        // Свойства доступа
        public int LineNumber
        {
            get { return _lineNumber; }
            set
            {
                _lineNumber = value;
                _lineNumberTextBox.Text = _lineNumber.ToString();
            }
        }
        public int MaxLineNumber
        {
            get { return _maxLineNumber; }
            set { _maxLineNumber = value; }
        }
    
        private void OnActivated(object sender, EventArgs e)
        {
            // Если существуют обработчики, инициируем событие
            if (GotoActivate != null)
                GotoActivate(this, EventArgs.Empty);
    
            _rangeNumber.Content = _rangeOrigin +
                String.Format(" (1 - {0}):", _maxLineNumber);
            _lineNumberTextBox.Focus();
            _lineNumberTextBox.SelectAll();// Выделяем содержимое
        }
    
        private void OkClicked(object sender, RoutedEventArgs e)
        {
            // Не закрывать диалог, пока есть ошибки
            if (string.IsNullOrEmpty(_lineNumberTextBox.Text))
            {
                MessageBox.Show(res.GetString("GotoErrorMsgEmpty"), 
                    res.GetString("GotoErrorDialogTitle"));
                return;
            }
            if (!int.TryParse(_lineNumberTextBox.Text, out _lineNumber))
            {
                MessageBox.Show(res.GetString("GotoErrorMsgFormat"), 
                    res.GetString("GotoErrorDialogTitle"));
                return;
            }
            if (LineNumber > _maxLineNumber || LineNumber <= 0)
            {
                MessageBox.Show(res.GetString("GotoErrorMsgRange"), 
                    res.GetString("GotoErrorDialogTitle"));
                return;
            }
    
            this.DialogResult = true;
            this.Close();
        }
    
        private void CancelClicked(object sender, RoutedEventArgs e)
        {
            this.DialogResult = false;
            this.Close();
        }
    }
}