稳扎稳打Silverlight(42) - 4.0控件之Viewbox, RichTextBox

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稳扎稳打Silverlight(42) - 4.0控件之Viewbox, RichTextBox

作者：webabcd


介绍
Silverlight 4.0 控件一览：

• Viewbox - 一个容器控件，其内只能有一个子元素。Viewbox 可以决定其内的子元素如何拉伸、缩放、对齐
• RichTextBox - 编辑器。用于显示或编辑文本、超链、图片、UI元素等 

在线DEMO
http://www.cnblogs.com/webabcd/archive/2010/08/09/1795417.html


示例
 1、Viewbox 的 Demo
ViewboxDemo.xaml

代码

< navigation:Page  x:Class ="Silverlight40.Control.ViewboxDemo"  
           xmlns ="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
           xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml"  
           xmlns:d ="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc ="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:navigation ="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
           Title ="ViewboxDemo Page" >
     < Grid  x:Name ="LayoutRoot"  Background ="White" >
         < StackPanel  Background ="AntiqueWhite"  HorizontalAlignment ="Left" >

             <!--  用于演示 Viewbox.Stretch 属性  -->
             < StackPanel  Margin ="5"  Width ="200" >
                 < TextBlock  Text ="Stretch"   />
                 < Button  Name ="btn1"  Click ="stretchNone"  Content ="None"   />
                 < Button  Name ="btn2"  Click ="stretchFill"  Content ="Fill"   />
                 < Button  Name ="btn3"  Click ="stretchUniform"  Content ="Uniform"   />
                 < Button  Name ="btn4"  Click ="stretchUniformToFill"  Content ="UniformToFill"   />
             </ StackPanel >

             <!--  用于演示 Viewbox.StretchDirection 属性  -->
             < StackPanel  Margin ="5"  Width ="200" >
                 < TextBlock  Text ="StretchDirection"   />
                 < Button  Name ="btn5"  Click ="stretchDirectionUpOnly"  Content ="UpOnly"   />
                 < Button  Name ="btn6"  Click ="stretchDirectionDownOnly"  Content ="DownOnly"   />
                 < Button  Name ="btn7"  Click ="stretchDirectionBoth"  Content ="Both"   />
             </ StackPanel >

             <!--  用于演示 Viewbox.HorizontalAlignment 属性  -->
             < StackPanel  Margin ="5"  Width ="200" >
                 < TextBlock  Text ="HorizontalAlignment"   />
                 < Button  Name ="btn8"  Click ="horizontalAlignmentCenter"  Content ="Center"   />
                 < Button  Name ="btn9"  Click ="horizontalAlignmentLeft"  Content ="Left"   />
                 < Button  Name ="btn10"  Click ="horizontalAlignmentRight"  Content ="Right"   />
                 < Button  Name ="btn11"  Click ="horizontalAlignmentStretch"  Content ="Stretch"   />
             </ StackPanel >

             <!--  用于演示 Viewbox.VerticalAlignment 属性  -->
             < StackPanel  Margin ="5"  Width ="200" >
                 < TextBlock  Text ="VerticalAlignment"   />
                 < Button  Name ="btn12"  Click ="verticalAlignmentCenter"  Content ="Center"   />
                 < Button  Name ="btn13"  Click ="verticalAlignmentTop"  Content ="Top"   />
                 < Button  Name ="btn14"  Click ="verticalAlignmentBottom"  Content ="Bottom"   />
                 < Button  Name ="btn15"  Click ="verticalAlignmentStretch"  Content ="Stretch"   />
             </ StackPanel >

             <!--  用于显示当前 Viewbox 的 Stretch 值，StretchDirection 值，HorizontalAlignment 值，VerticalAlignment 值  -->
             < StackPanel  Margin ="5" >
                 < TextBlock  Name ="lblMsg"   />
             </ StackPanel >

             <!--  用于演示 Viewbox 的各种效果  -->
             < StackPanel  Width ="500"  Height ="300"  Background ="Black" >
                 < Viewbox  Name ="viewbox"  Width ="500"  Height ="300" >
                     <!--  注：Viewbox 内只能有一个子元素  -->
                     < Image  Source ="/Resource/Logo.jpg"   />
                 </ Viewbox >
             </ StackPanel >
            
         </ StackPanel >
     </ Grid >
</ navigation:Page >

ViewboxDemo.xaml.cs

代码

/*
 * Viewbox - 一个容器控件，其内只能有一个子元素。Viewbox 可以决定其内的子元素如何拉伸、缩放、对齐
  */

using  System;
using  System.Collections.Generic;
using  System.Linq;
using  System.Net;
using  System.Windows;
using  System.Windows.Controls;
using  System.Windows.Documents;
using  System.Windows.Input;
using  System.Windows.Media;
using  System.Windows.Media.Animation;
using  System.Windows.Shapes;
using  System.Windows.Navigation;

namespace  Silverlight40.Control
{
     public   partial   class  ViewboxDemo : Page
    {
         public  ViewboxDemo()
        {
            InitializeComponent();
        }

         protected   override   void  OnNavigatedTo(NavigationEventArgs e)
        {
            ShowResult();
        }

         //  用于显示当前 Viewbox 的 Stretch 值，StretchDirection 值，HorizontalAlignment 值，VerticalAlignment 值
         private   void  ShowResult()
        {
            lblMsg.Text  =   string .Format( " Stretch: {0}, StretchDirection: {1}, HorizontalAlignment: {2}, VerticalAlignment: {3} " ,
                viewbox.Stretch.ToString(),
                viewbox.StretchDirection.ToString(),
                viewbox.HorizontalAlignment.ToString(),
                viewbox.VerticalAlignment.ToString());
        }


         /*
         * Viewbox.Stretch - 子元素在 Viewbox 内的拉伸模式 [System.Windows.Media.Stretch 枚举]
         *     Stretch.None - 不做处理。不做任何拉伸处理，填充内容保持原始大小
         *     Stretch.Fill - 充满。调整填充内容，以充满整个容器，填充内容比例变为容器比例
         *     Stretch.Uniform - 等比适应。调整填充内容，以适合容器尺寸，填充内容会做等比例调整（默认值）
         *         如果填充内容与容器比例不一样，那么填充内容调整的结果为：
　　　　 *　　     使得填充内容的宽与容器的宽相等，或者 填充内容的高与容器的高相等。填充内容会被完整显示
         *     Stretch.UniformToFill - 等比充满。调整填充内容，以适合容器尺寸，填充内容会做等比例调整
         *         如果填充内容与容器比例不一样，那么填充内容调整的结果为：
　　　　 * 　　　  使得填充内容的宽与容器的宽相等，并且 填充内容的高与容器的高相等。填充内容会被做相应的剪裁
          */
         private   void  stretchNone( object  sender, RoutedEventArgs e)
        {
            viewbox.Stretch  =  Stretch.None;
            ShowResult();
        }
         private   void  stretchFill( object  sender, RoutedEventArgs e)
        {
            viewbox.Stretch  =  Stretch.Fill;
            ShowResult();
        }
         private   void  stretchUniform( object  sender, RoutedEventArgs e)
        {
            viewbox.Stretch  =  Stretch.Uniform;
            ShowResult();
        }
         private   void  stretchUniformToFill( object  sender, RoutedEventArgs e)
        {
            viewbox.Stretch  =  Stretch.UniformToFill;
            ShowResult();
        }


         /*
         * Viewbox.StretchDirection - 子元素在 Viewbox 内的缩放模式 [System.Windows.Controls.StretchDirection 枚举]
         *     StretchDirection.UpOnly - 当子元素小于 Viewbox 时，子元素会放大
         *     StretchDirection.DownOnly - 当子元素大于 Viewbox 时，子元素会缩小
         *     StretchDirection.Both - 不做任何处理（默认值）
          */
         private   void  stretchDirectionUpOnly( object  sender, RoutedEventArgs e)
        {
            viewbox.StretchDirection  =  StretchDirection.UpOnly;
            ShowResult();
        }
         private   void  stretchDirectionDownOnly( object  sender, RoutedEventArgs e)
        {
            viewbox.StretchDirection  =  StretchDirection.DownOnly;
            ShowResult();
        }
         private   void  stretchDirectionBoth( object  sender, RoutedEventArgs e)
        {
            viewbox.StretchDirection  =  StretchDirection.Both;
            ShowResult();
        }


         /*
         * Viewbox.HorizontalAlignment - 子元素在 Viewbox 内的水平方向的对齐模式 [System.Windows.HorizontalAlignment 枚举]
         *      Center, Left, Right, Stretch（默认值）
          */
         private   void  horizontalAlignmentCenter( object  sender, RoutedEventArgs e)
        {
            viewbox.HorizontalAlignment  =  HorizontalAlignment.Center;
            ShowResult();
        }
         private   void  horizontalAlignmentLeft( object  sender, RoutedEventArgs e)
        {
            viewbox.HorizontalAlignment  =  HorizontalAlignment.Left;
            ShowResult();
        }
         private   void  horizontalAlignmentRight( object  sender, RoutedEventArgs e)
        {
            viewbox.HorizontalAlignment  =  HorizontalAlignment.Right;
            ShowResult();
        }
         private   void  horizontalAlignmentStretch( object  sender, RoutedEventArgs e)
        {
            viewbox.HorizontalAlignment  =  HorizontalAlignment.Stretch;
            ShowResult();
        }


         /*
         * Viewbox.VerticalAlignment - 子元素在 Viewbox 内的垂直方向的对齐模式 [System.Windows.VerticalAlignment 枚举]
         *      Center, Top, Bottom, Stretch（默认值）
          */
         private   void  verticalAlignmentCenter( object  sender, RoutedEventArgs e)
        {
            viewbox.VerticalAlignment  =  VerticalAlignment.Center;
            ShowResult();
        }
         private   void  verticalAlignmentTop( object  sender, RoutedEventArgs e)
        {
            viewbox.VerticalAlignment  =  VerticalAlignment.Top;
            ShowResult();
        }
         private   void  verticalAlignmentBottom( object  sender, RoutedEventArgs e)
        {
            viewbox.VerticalAlignment  =  VerticalAlignment.Bottom;
            ShowResult();
        }
         private   void  verticalAlignmentStretch( object  sender, RoutedEventArgs e)
        {
            viewbox.VerticalAlignment  =  VerticalAlignment.Stretch;
            ShowResult();
        }
    }
}

2、RichTextBox 的 Demo
RichTextBoxDemo.xaml

代码

< navigation:Page  x:Class ="Silverlight40.Control.RichTextBoxDemo"  
           xmlns ="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
           xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml"  
           xmlns:d ="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc ="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:navigation ="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
           Title ="RichTextBoxDemo Page" >
     < StackPanel  HorizontalAlignment ="Left" >
        
         < StackPanel  Background ="AntiqueWhite"  Orientation ="Horizontal" >
             < ComboBox  x:Name ="cmbFontSize"  FontSize =" {Binding SelectedItem.FontSize, RelativeSource={RelativeSource Self}} "  SelectionChanged ="cmbFontSize_SelectionChanged" >
                 < ComboBoxItem  Content ="16"  Tag ="16"  FontSize ="16"  IsSelected ="True"   />
                 < ComboBoxItem  Content ="48"  Tag ="48"  FontSize ="48"   />
             </ ComboBox >
             < ComboBox  x:Name ="cmbFontFamily"  FontFamily =" {Binding SelectedItem.FontFamily, RelativeSource={RelativeSource Self}} "  SelectionChanged ="cmbFontFamily_SelectionChanged" >
                 < ComboBoxItem  Content ="Arial"  Tag ="Arial"  FontFamily ="Arial"  IsSelected ="True"   />
                 < ComboBoxItem  Content ="Verdana"  Tag ="Verdana"  FontFamily ="Verdana"   />
             </ ComboBox >
             < Button  Name ="btnBold"  Content ="加粗"  Click ="btnBold_Click"   />
             < Button  Name ="btnItalic"  Content ="斜体"  Click ="btnItalic_Click"   />
             < Button  Name ="btnUnderline"  Content ="下划线"  Click ="btnUnderline_Click"   />
             < Button  Name ="btnHyperlink"  Content ="插入超级链接的 Demo"  Click ="btnHyperlink_Click"   />
             < Button  Name ="btnUIElement"  Content ="插入 UIElement 的 Demo"  Click ="btnUIElement_Click"   />
             < ToggleButton  Name ="btnXaml"  Content ="xaml"  Checked ="btnXaml_Checked"  Unchecked ="btnXaml_Checked"   />
             < ToggleButton  Name ="btnPreview"  Content ="预览"  Checked ="btnPreview_Checked"  Unchecked ="btnPreview_Checked"   />
             < Button  Name ="btnTextPointerDemo"  Content ="TextPointer 的 Demo (将光标当前所在位置到文本结尾的文字全变为绿色)"  Click ="btnTextPointerDemo_Click"   />
         </ StackPanel >
        
         < Grid  Width ="600"  Height ="400" >
             < RichTextBox  Name ="richTextBox"  VerticalScrollBarVisibility ="Auto" >
                 < Paragraph >
                    webabcd
                 </ Paragraph >
                 < Paragraph >
                     < Span > webabcd </ Span >
                     < LineBreak  />
                     < Bold > webabcd </ Bold >
                     < LineBreak  />
                     < Italic > webabcd </ Italic >
                     < LineBreak  />
                     < Underline > webabcd </ Underline >
                     < LineBreak  />
                     < Run  FontFamily ="Arial"  FontSize ="20"  FontStretch ="Normal"  FontStyle ="Italic"  FontWeight ="Bold"  Foreground ="Red"  TextDecorations ="underline"  Text ="webabcd"   />
                     < LineBreak  />
                     < Hyperlink  TargetName ="_black"  NavigateUri ="http://webabcd.cnblogs.com/" > webabcd </ Hyperlink >
                     < LineBreak  />
                     < InlineUIContainer >
                         < Image  Source ="/Resource/Logo.jpg"  Height ="100"  Width ="100"  ToolTipService.ToolTip ="我是提示"   />
                     </ InlineUIContainer >
                 </ Paragraph >
             </ RichTextBox >
             < TextBox  Name ="txtXaml"  TextWrapping ="Wrap"  VerticalScrollBarVisibility ="Auto"  Visibility ="Collapsed"   />
         </ Grid >
        
         < TextBlock  Name ="lblMsg"   />
        
     </ StackPanel >
</ navigation:Page >

RichTextBoxDemo.xaml.cs

代码

/*
 * RichTextBox - 编辑器。用于显示或编辑文本、超链、图片、UI元素等
  */

using  System;
using  System.Collections.Generic;
using  System.Linq;
using  System.Net;
using  System.Windows;
using  System.Windows.Controls;
using  System.Windows.Documents;
using  System.Windows.Input;
using  System.Windows.Media;
using  System.Windows.Media.Animation;
using  System.Windows.Shapes;
using  System.Windows.Navigation;
using  System.Windows.Media.Imaging;

namespace  Silverlight40.Control
{
     public   partial   class  RichTextBoxDemo : Page
    {
         public  RichTextBoxDemo()
        {
            InitializeComponent();
        }

         protected   override   void  OnNavigatedTo(NavigationEventArgs e)
        {
             /*
             * RichTextBox 的内容结构说明如下：
             * 
             * Block - 抽象类。块级内容的基类
             *     Paragraph - 段落，包含一组内联元素。继承自 Block
             * Inline - 抽象类。内联元素的基类
             *     Run - 文本。继承自 Inline
             *     LineBreak - 换行。继承自 Inline
             *     Span - 文本。继承自 Inline
             *         Hyperlink - 超链接。继承自 Span
             *         Bold - 加粗。继承自 Span
             *         Italic - 斜体。继承自 Span
             *         Underline - 下划线。继承自 Span
             *     InlineUIContainer - 用于承载 UIElement 类型的对象。继承自 Span
             * TextElement - TextElement是 Inline 的基类，可以对其设置如下属性
             *     FontSize - 字体大小
             *     FontFamily - 字体名称
             *     Foreground - 字体颜色（因为 xaml 属性仅支持可以表示为一个字符串的属性值。所以这里只能使用 SolidColorBrush，而不能使用 LinearGradientBrush 之类的）
             *     FontWeight - 笔画粗细
             *     FontStyle - 是否斜体
             *     FontStretch - 字体的拉伸程度（需要字体支持）
              */


             /*  
             * Paragraph.Inlines - 段落所包含的内联元素的集合
             * RichTextBox.Blocks - RichTextBox 中的块级元素的集合
             * RichTextBox.Xaml - RichTextBox 中的内容的 xaml 代码
              */

            Bold bold  =   new  Bold();
            bold.Inlines.Add( " web " );

            LineBreak lineBreak  =   new  LineBreak();

            Run run  =   new  Run();
            run.Text  =   " abcd " ;
            
            Paragraph paragraph  =   new  Paragraph();
            paragraph.Inlines.Add(bold);
            paragraph.Inlines.Add(lineBreak);
            paragraph.Inlines.Add(run);

            richTextBox.Blocks.Add(paragraph);
        }


         /*
         * RichTextBox.Selection - 获取 RichTextBox 中的选中内容，返回一个 TextSelection 类型的对象
         * TextSelection.ApplyPropertyValue(DependencyProperty formattingProperty,    Object value) - 为选中的内容指定其格式的属性和值
         *     DependencyProperty formattingProperty - 格式的属性
         *     Object value - 格式的属性的值
         * TextSelection.Text - 选中的内容中的纯文本内容
         * TextSelection.Xaml - 选中的内容的 xaml 代码
         * TextSelection.Insert() - 把当前选中的内容替换成指定的 TextElement
         * 以下分别举例如何设置选中文本的字体大小、字体名称、加粗、斜体、下划线
          */
         private   void  cmbFontSize_SelectionChanged( object  sender, SelectionChangedEventArgs e)
        {
             if  (richTextBox  !=   null   &&  richTextBox.Selection.Text.Length  >   0 )
            {
                richTextBox.Selection.ApplyPropertyValue(Run.FontSizeProperty,  double .Parse((cmbFontSize.SelectedItem  as  ComboBoxItem).Tag.ToString()));
            }
        }
         private   void  cmbFontFamily_SelectionChanged( object  sender, SelectionChangedEventArgs e)
        {
             if  (richTextBox  !=   null   &&  richTextBox.Selection.Text.Length  >   0 )
            {
                richTextBox.Selection.ApplyPropertyValue(Run.FontFamilyProperty,  new  FontFamily((cmbFontFamily.SelectedItem  as  ComboBoxItem).Tag.ToString()));
            }
        }
         private   void  btnBold_Click( object  sender, RoutedEventArgs e)
        {
             if  (richTextBox.Selection.Text.Length  >   0 )
            {
                 if  (richTextBox.Selection.GetPropertyValue(Run.FontWeightProperty)  is  FontWeight  &&  ((FontWeight)richTextBox.Selection.GetPropertyValue(Run.FontWeightProperty))  ==  FontWeights.Normal)
                    richTextBox.Selection.ApplyPropertyValue(Run.FontWeightProperty, FontWeights.Bold);
                 else
                    richTextBox.Selection.ApplyPropertyValue(Run.FontWeightProperty, FontWeights.Normal);
            }
        }
         private   void  btnItalic_Click( object  sender, RoutedEventArgs e)
        {
             if  (richTextBox.Selection.Text.Length  >   0 )
            {
                 if  (richTextBox.Selection.GetPropertyValue(Run.FontStyleProperty)  is  FontStyle  &&  ((FontStyle)richTextBox.Selection.GetPropertyValue(Run.FontStyleProperty))  ==  FontStyles.Normal)
                    richTextBox.Selection.ApplyPropertyValue(Run.FontStyleProperty, FontStyles.Italic);
                 else
                    richTextBox.Selection.ApplyPropertyValue(Run.FontStyleProperty, FontStyles.Normal);
            }
        }
         private   void  btnUnderline_Click( object  sender, RoutedEventArgs e)
        {
             if  (richTextBox.Selection.Text.Length  >   0 )
            {
                 if  (richTextBox.Selection.GetPropertyValue(Run.TextDecorationsProperty)  ==   null )
                    richTextBox.Selection.ApplyPropertyValue(Run.TextDecorationsProperty, TextDecorations.Underline);
                 else
                    richTextBox.Selection.ApplyPropertyValue(Run.TextDecorationsProperty,  null );
            }
        }


         /*
         * TextSelection.Insert() - 把当前选中的内容替换成指定的 TextElement
         * Hyperlink - 一个用于显示超链接的内联元素。Hyperlink继承自Span，Span继承自Inline，Inline继承自TextElement
         * 以下举例如何插入超链接（要在 RichTextBox 使超链接有效，需要将 RichTextBox 设置为显示状态）
          */
         private   void  btnHyperlink_Click( object  sender, RoutedEventArgs e)
        {
            Hyperlink hyperlink  =   new  Hyperlink();
            hyperlink.TargetName  =   " _blank " ;
            hyperlink.NavigateUri  =   new  Uri( " http://webabcd.cnblogs.com/ " );
            hyperlink.Inlines.Add( " webabcd blog " );
            richTextBox.Selection.Insert(hyperlink);
        }


         /*
         * InlineUIContainer - 一个容器，可以承载任何 UIElement 类型的对象。InlineUIContainer继承自Inline
         * 以下举例如何插入图片
          */
         private   void  btnUIElement_Click( object  sender, RoutedEventArgs e)
        {
            Image img  =   new  Image();
            img.Source  =   new  BitmapImage( new  Uri( " /Resource/Logo.jpg " , UriKind.Relative));
            img.Width  =   100 ;
            img.Height  =   100 ;

            InlineUIContainer container  =   new  InlineUIContainer();
            container.Child  =  img;

            richTextBox.Selection.Insert(container);
        }


         /*
         * RichTextBox.Xaml - RichTextBox 中的内容的 xaml 代码
         * 以下举例如何在“显示模式”和“代码模式”之间切换
          */
         private   void  btnXaml_Checked( object  sender, RoutedEventArgs e)
        {
             if  (btnXaml.IsChecked.Value)
            {
                txtXaml.Text  =  richTextBox.Xaml;
                txtXaml.Visibility  =  Visibility.Visible;
            }
             else
            {
                richTextBox.Xaml  =  txtXaml.Text;
                txtXaml.Visibility  =  Visibility.Collapsed;
            }
        }


         /*
         * RichTextBox.IsReadOnly - 指定是否可以在 RichTextBox 中编辑内容
         *     true - 显示模式
         *     false - 编辑模式（此模式下可以通过快捷键的方式来支持撤销 Ctrl+Z 和重做 Ctrl+Y 操作）
         * 以下举例如何预览 RichTextBox 中的内容（注：只有在显示模式中超链接才生效）
          */
         private   void  btnPreview_Checked( object  sender, RoutedEventArgs e)
        {
            richTextBox.IsReadOnly  =  btnPreview.IsChecked.Value;
        }


         private   void  btnTextPointerDemo_Click( object  sender, RoutedEventArgs e)
        {
             /*
             * TextPointer - 表示 RichTextBox 中的一个位置
             * 插入位置（Insertion Position）的概念：
             *     TextPointer 出现在内容中的字符之间则为插入位置
             *     TextPointer 出现在定义内容结构的元素标记之间，则此位置不是插入位置。例如，两个相邻段落标记（即前一个段落的结束标记与下一个段落的开始标记）之间的位置就是一个有效的 TextPointer 位置，但不是插入位置
             * TextPointer.CompareTo(TextPointer tp) - 当前 TextPointer 位于指定的 TextPointer 之前则为 -1，之后则为 1，相同则为 0
             * TextPointer.IsAtInsertionPosition - 当前 TextPointer 是否是一个插入位置
             * TextPointer.GetNextInsertionPosition(LogicalDirection direction) - 获取当前 TextPointer 的按指定的逻辑方向的下一个插入位置
             *     LogicalDirection - 逻辑方向 [System.Windows.Documents.LogicalDirection 枚举]
             *         LogicalDirection.Forward - 向前
             *         LogicalDirection.Backward - 向后
             * TextPointer.GetPositionAtOffset(int offset, LogicalDirection direction) - 获取当前 TextPointer 的按指定的逻辑方向偏移了指定值的 TextPointer
             * TextPointer.Parent - 包含当前 TextPointer 的容器。比如，文字的 Parent 是 run ；RichTextBox.ContentEnd 的 Parent 是 RichTextBox
             * 
             * RichTextBox.ContentStart - RichTextBox 内容的开头的 TextPointer（肯定不是插入位置）
             * RichTextBox.ContentEnd - RichTextBox 内容的结尾的 TextPointer（肯定不是插入位置）
             * RichTextBox.GetPositionFromPoint(Point point) - 获取离指定 Point 最近的插入位置
             * RichTextBox.Selection - 获取 RichTextBox 中的选中内容，返回一个 TextSelection 类型的对象
             * TextSelection.Start - 选中内容的开头 TextPointer
             * TextSelection.End - 选中内容的开头 TextPointer
             * TextSelection.Select(TextPointer tp1, TextPointer tp2) - 指定两个 TextPointer 来更新选中内容
             * 
             * 在 RichTextBox 中被视为一个符号的有：TextElement 的开始或结束标记；InlineUIContainer 中的 UIElement 元素；Run 中的字符
              */

             //  将光标当前所在位置到文本结尾的文字全变为绿色
            TextPointer currentPointer  =  richTextBox.Selection.Start;
            TextPointer endPointer  =  richTextBox.ContentEnd.GetNextInsertionPosition(LogicalDirection.Backward);
            richTextBox.Selection.Select(currentPointer, endPointer);
            richTextBox.Selection.ApplyPropertyValue(Run.ForegroundProperty, Colors.Green);

             //  将光标当前所在位置到文本结尾的文字信息输出到页面上
             while  (currentPointer.CompareTo(endPointer)  ==   - 1 )
            {
                 string  currentChar  =   "" ;

                TextPointer nextPointer  =  currentPointer.GetNextInsertionPosition(LogicalDirection.Forward);
                 if  (nextPointer  !=   null )
                {
                    richTextBox.Selection.Select(currentPointer, nextPointer);
                     if  (richTextBox.Selection.Text.Length  !=   0 )
                        currentChar  =  richTextBox.Selection.Text;
                }

                lblMsg.Text  +=  currentChar;

                currentPointer  =  currentPointer.GetNextInsertionPosition(LogicalDirection.Forward);
            }
        }
    }
}

OK
[源码下载]