silverlight中的richtextbox和rtf格式的转换
silvergliht 4.0中有了richtextbox控件，但是它只接受xaml格式的输入，下面这个函数实现了rtf和xaml的转换，用到了flowdocument。
需要注意的是直接从rtf转换过来的话有些attribute silverlight不认。我也不知道找全了没有，目前发现的是 section 里面的一堆attribute，然后就是margin和textindent。另外中文字体也会出错。
1 /// <summary>
2 /// convert the string "from" from sourceFormat to targetFormat
3 /// </summary>
4 /// <param name="from"></param>
5 /// <param name="sourceFormat">System.Windows.DataFormats.Rtf</param>
6 /// <param name="targetFormat">System.Windows.DataFormats.Xaml </param>
7 /// <returns></returns>
8 private string convertFormat(string from, string sourceFormat, string targetFormat)
9 {
10 string xaml = String.Empty;
11 System.Windows.Documents.FlowDocument doc = new System.Windows.Documents.FlowDocument();
12 System.Windows.Documents.TextRange range = new System.Windows.Documents.TextRange(doc.ContentStart, doc.ContentEnd);
13
14 using (MemoryStream ms = new MemoryStream())
15 {
16 using (StreamWriter sw = new StreamWriter(ms))
17 {
18 sw.Write(from);
19 sw.Flush();
20 ms.Seek(0, SeekOrigin.Begin);
21 range.Load(ms, sourceFormat);
22 }
23 }
24
25
26 using (MemoryStream ms = new MemoryStream())
27 {
28 range = new System.Windows.Documents.TextRange(doc.ContentStart, doc.ContentEnd);
29
30 range.Save(ms, targetFormat);
31 ms.Seek(0, SeekOrigin.Begin);
32 using (StreamReader sr = new StreamReader(ms))
33 {
34 xaml = sr.ReadToEnd();
35 }
36 }
37
38 // remove all attribuites in section and remove attribute margin
39 if (targetFormat.Equals(System.Windows.DataFormats.Xaml))
40 {
41 int start = xaml.IndexOf("<Section");
42 int stop = xaml.IndexOf(">") + 1;
43
44 string section = xaml.Substring(start, stop);
45
46 xaml = xaml.Replace(section, "<Section xml:space=\"preserve\" HasTrailingParagraphBreakOnPaste=\"False\" xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\">");
47
48 // remove Margin attribute
49 Regex reg = new Regex("Margin=\"[^\"]*\"");
50 xaml = reg.Replace(xaml, string.Empty);
5152 // remove TextIndent attribute
53 reg = new Regex("TextIndent=\"[^\"]*\"");
54 xaml = reg.Replace(xaml, string.Empty);
55
56 // change the non english font family
57 reg = new Regex("FontFamily=\"[^a-zA-Z]*\"");
58 xaml = reg.Replace(xaml, "FontFamily=\"Arial\"");
59
60 }
61 return xaml;
62 }