TextBox

常用属性：

TextWrapping="Wrap"  换行

VerticalScrollBarVisibility="Visible" 纵向滚动条

textBox1.SelectionStart

textBox1.SelectionLength

textBox1.SelectedText

    <StackPanel Margin="10" >
        <TextBox x:Name="textBox1" TextWrapping="Wrap" VerticalScrollBarVisibility="Visible" Margin="5" Height="70" SelectionChanged="TextBox_SelectionChanged">
            When you are old and grey and full of sleep, And nodding by the fire，take down this book, And slowly read,and dream of the soft look Your eyes had once,and of their shadows deep; How many loved your moments of glad grace, And loved your beauty with love false or true, But one man loved the pilgrim Soul in you And loved the sorrows of your changing face; And bending down beside the glowing bars, Murmur,a little sadly,how Love fled And paced upon the mountains overhead And hid his face amid a crowd of stars.
        </TextBox>
        <ScrollViewer VerticalScrollBarVisibility="Auto" Margin="5" Height="60" >
            <TextBlock x:Name="textBlock1" TextWrapping="Wrap" />
        </ScrollViewer>
    </StackPanel>

private void TextBox_SelectionChanged(object sender, RoutedEventArgs e)
        {
            if (textBox1.SelectionLength==0)
            {
                return;
            }
            this.textBlock1.Text = this.textBox1.SelectionStart + "到" + this.textBox1.SelectionLength + "\n选中的内容\n"+this.textBox1.SelectedText;
        }