WPF——菜单栏及TabControl

 <Grid>
        <Menu>
            <MenuItem Header="文件" Click="MenuItem_Click_3"> 
                <MenuItem Header="打开新窗口" Click="MenuItem_Click_1"></MenuItem>
                <MenuItem Header="退出" Click="MenuItem_Click_4"  ></MenuItem>
            </MenuItem>
            <MenuItem Header="帮助">
                <MenuItem Header="关于我们"></MenuItem>
            </MenuItem>           
        </Menu>
        <TabControl Name="TabControl1" HorizontalAlignment="Left" Height="337" Margin="0,20,0,0" VerticalAlignment="Top" Width="572">
            <TabItem Header="原始窗口">
                <Grid Background="#FFE5E5E5">
                    <TextBox HorizontalAlignment="Left"  Height="305" Margin="0" TextWrapping="Wrap" Text="" VerticalAlignment="Top" Width="562"/>
                    
                    
                </Grid>
            </TabItem>         
        </TabControl>

    </Grid>

 public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
        private int i = 0;//定义一个i用来使新造的Item名字不同
        TextBox t;//每造一个新Item 然后将Textbox扔进去
        private void MenuItem_Click_1(object sender, RoutedEventArgs e) //打开新窗口按钮
        {
             TabItem ti = new TabItem();//造一个新选项卡
             ti.Header = "新窗口"+(i+1);//新选项卡的名字
             TabControl1.Items.Add(ti);//将造好的新选项卡扔进TabControl1里
             t = new TextBox();//实体化一个新文本框
             t.Width = 562;
             t.Height = 305;
            //下面开始将文本框添加到新造的选项卡中
            
            //每造一个新窗口便默认突出显示为新窗口
             TabControl1.SelectedIndex = i+1;
             i++;
        }

     
        private void MenuItem_Click_4(object sender, RoutedEventArgs e)//关闭按钮
        {
            this.Close();
        }

        private void MenuItem_Click_3(object sender, RoutedEventArgs e)
        {

        }
    }