1、RichTextBox扩展类

using System;using System.Collections.Generic;using System.Globalization;using System.Linq;using System.Text;using System.Windows.Documents;using System.Windows.Media;namespace PrintTime{    /// 
    /// RichTextBox长度自动增长 扩展类    /// 
    public static class FlowDocumentExtensions    {        private static IEnumerable
     
       GetRunsAndParagraphs(FlowDocument doc)        {            for (TextPointer position = doc.ContentStart;              position != null && position.CompareTo(doc.ContentEnd) <= 0;              position = position.GetNextContextPosition(LogicalDirection.Forward))            {                if (position.GetPointerContext(LogicalDirection.Forward) == TextPointerContext.ElementEnd)                {                    Run run = position.Parent as Run;                    if (run != null)                    {                        yield return run;                    }                    else                    {                        Paragraph para = position.Parent as Paragraph;                        if (para != null)                        {                            yield return para;                        }                    }                }            }        }        public static FormattedText GetFormattedText(this FlowDocument doc)        {            if (doc == null)            {                throw new ArgumentNullException("doc");            }            //doc.PagePadding = new System.Windows.Thickness(0, 0, 0, 0);//设置文本的边距            FormattedText output = new FormattedText(              GetText(doc),              CultureInfo.CurrentCulture,              doc.FlowDirection,              new Typeface(doc.FontFamily, doc.FontStyle, doc.FontWeight, doc.FontStretch),              doc.FontSize,              doc.Foreground);            int offset = 0;            foreach (TextElement el in GetRunsAndParagraphs(doc))            {                Run run = el as Run;                if (run != null)                {                    int count = run.Text.Length;                    output.SetFontFamily(run.FontFamily, offset, count);                    output.SetFontStyle(run.FontStyle, offset, count);                    output.SetFontWeight(run.FontWeight, offset, count);                    output.SetFontSize(run.FontSize, offset, count);                    output.SetForegroundBrush(run.Foreground, offset, count);                    output.SetFontStretch(run.FontStretch, offset, count);                    output.SetTextDecorations(run.TextDecorations, offset, count);                    offset += count;                }                else                {                    offset += Environment.NewLine.Length;                }            }            return output;        }        private static string GetText(FlowDocument doc)        {            StringBuilder sb = new StringBuilder();            foreach (TextElement el in GetRunsAndParagraphs(doc))            {                Run run = el as Run;                sb.Append(run == null ? Environment.NewLine : run.Text);            }            return sb.ToString();        }    }}
     

2、RichTextBox控件定义

RichTextBox rtb = new RichTextBox()            {                Margin = new Thickness(5),                AllowDrop = true,                HorizontalAlignment = HorizontalAlignment.Left,                BorderThickness = new Thickness(1),                VerticalAlignment = VerticalAlignment.Top,                BorderBrush = Brushes.Transparent,                FontSize = model.FontSize,                //FontFamily = new FontFamily(cb_FontFamily.SelectedValue.ToString()),                FontFamily = new FontFamily(model.FontName),                Background = Brushes.Transparent,            };            string strName = "rtb_" + dateName;            if (textTpe.Equals("timeStamp"))            {                Thread.Sleep(1);                dateName = DateTime.Now.ToString("yyyyMMddHHmmss");                strName = "rtb_date_" + dateName + "_" + model.TimestampSelectIndex;                rtb.IsReadOnly = true;                gridWords.Tag = model.TimestampText== null ?  "": model.TimestampText;                rtb.Tag = model.TimestampFormat == null ? "" : model.TimestampFormat;            }            rtb.Name = strName;            rtb.Document = new FlowDocument() { LineHeight = 1 };//修改行间距            //rtb.TextChanged += new TextChangedEventHandler((o, q) => rtb.Width = rtb.Document.GetFormattedText().WidthIncludingTrailingWhitespace + 16);            rtb.VerticalScrollBarVisibility = ScrollBarVisibility.Disabled;            rtb.PreviewMouseLeftButtonDown += Rtb_PreviewMouseLeftButtonDown;            rtb.PreviewMouseRightButtonDown += Rtb_PreviewMouseRightButtonDown;            rtb.Loaded += Rtb_Loaded;            rtb.GotFocus += Rtb_GotFocus;            rtb.LostFocus += Rtb_LostFocus;            rtb.TextChanged += Rtb_TextChanged;            rtb.ContextMenu = (ContextMenu)this.FindResource("ContextMenu");                        gridWords.Children.Add(rtb);

3、事件处理

private string rtbLastText = "";        private void Rtb_TextChanged(object sender, TextChangedEventArgs e)        {            RichTextBox richTextBox = sender as RichTextBox;            if (richTextBox != null)            {                DockPanel dockPanel = richTextBox.Parent as DockPanel;                if (dockPanel != null)                {                    if (dockPanel.Width != double.NaN)                    {                        dockPanel.Width = double.NaN;                    }                    if (dockPanel.Height != double.NaN)                    {                        dockPanel.Height = double.NaN;                    }                }                if (System.Environment.OSVersion.Version.Major == 6 && System.Environment.OSVersion.Version.Minor == 1)//win7模板加粗文本最后一字换行问题                {                    richTextBox.Width = richTextBox.Document.GetFormattedText().WidthIncludingTrailingWhitespace + 18;                }                else                {                    richTextBox.Width = richTextBox.Document.GetFormattedText().WidthIncludingTrailingWhitespace + 16;                }                richTextBox.Document.LineHeight = 1;//处理复制粘贴后行高变为Nan问题                //richTextBox.Document.PagePadding = new Thickness(0);                TextRange a = new TextRange(richTextBox.Document.ContentStart, richTextBox.Document.ContentEnd);                if (rtbLastText != a.Text.ToString() && !isUndo)                {                    rtbLastText = a.Text.ToString();                    CommandStack.AddUndo(richTextBox, CommandTypes.RichTextBoxEdit, new object[] { });                }            }        }