WPF中的richtextbox与winform中的richtextbox的使用不同，看看下面的基本操作：

一、取出richTextBox里面的内容
 (1)将richTextBox的内容以字符串的形式取出 

 string xw = System.Windows.Markup.XamlWriter.Save(richTextBox.Document);

 (2)将richTextBox的类容以二进制数据的方法取出 

     FlowDocument document = richTextBox.Document;
      System.IO.Stream s = new System.IO.MemoryStream(); 
      System.Windows.Markup.XamlWriter.Save(document, s);         
      byte[] data = new byte[s.Length];
      s.Position = 0;
      s.Read(data, 0, data.Length);
       s.Close();

二、richTextBox赋值
 (1)将字符串转换为数据流赋值给richTextBox中   

 System.IO.StringReader sr = new System.IO.StringReader(xw);
   System.Xml.XmlReader xr = System.Xml.XmlReader.Create(sr);
   richTextBox1.Document = (FlowDocument)System.Windows.Markup.XamlReader.Load(xr);

(2)将二进制数据赋值给richTextBox 

    System.IO.Stream ss = new System.IO.MemoryStream(data);
     FlowDocument doc = System.Windows.Markup.XamlReader.Load(ss) as FlowDocument;
      ss.Close();
      richTextBox1.Document = doc;

三、清空RichTextBox的方法 

System.Windows.Documents.FlowDocument doc = RichTextBox.Document;
doc.Blocks.Clear();

四、如何将一个String类型的字符串赋值给richTextBox 

myRTB.Document = new FlowDocument(new Paragraph(new Run(myString))); 
FlowDocument doc = new FlowDocument();
 Paragraph p = new Paragraph();  // Paragraph 类似于 html 的 P 标签
 Run r = new Run(myString);      // Run 是一个 Inline 的标签
 p.Inlines.Add(r);
 doc.Blocks.Add(p);
 myRTB.Document = doc;

五、将richTextBox中的内容以rtf的格式完全取出 

     string rtf = string.Empty;
             TextRange textRange = new TextRange(richTextBox.Document.ContentStart, richTextBox.Document.ContentEnd);
             using (System.IO.MemoryStream ms = new System.IO.MemoryStream())
             {
                 textRange.Save(ms, System.Windows.DataFormats.Rtf);
                 ms.Seek(0, System.IO.SeekOrigin.Begin);
                 System.IO.StreamReader sr = new System.IO.StreamReader(ms);
                 rtf = sr.ReadToEnd();
             }

六、其他操作 

 复制：   ToolBarCopy.Command = System.Windows.Input.ApplicationCommands.Copy;
 剪切：   toolBarCut.Command = System.Windows.Input.ApplicationCommands.Cut;
 粘贴：   ToolBarPaste.Command = System.Windows.Input.ApplicationCommands.Paste;
 撤销：   ToolBarUndo.Command = System.Windows.Input.ApplicationCommands.Undo;
 复原：   ToolBarRedo.Command = System.Windows.Input.ApplicationCommands.Redo;
 文字居中：  toolBarContentCenter.Command = System.Windows.Documents.EditingCommands.AlignCenter;
 文字居右：  toolBarContentRight.Command = System.Windows.Documents.EditingCommands.AlignRight;
 文字居左：  toolBarContentLeft.Command = System.Windows.Documents.EditingCommands.AlignLeft;
 有序排列：  ToolBarNumbering.Command = System.Windows.Documents.EditingCommands.ToggleNumbering;
 无序排列：  ToolBarBullets.Command = System.Windows.Documents.EditingCommands.ToggleBullets;
 字体变大：
             int fontSize = Convert.ToInt32(richTextBox.Selection.GetPropertyValue(TextElement.FontSizeProperty));
             fontSize++;
             richTextBox.Selection.ApplyPropertyValue(TextElement.FontSizeProperty, fontSize.ToString());



WPF-20：richtextbox相关操作（转）_xml