最近， 有同事偶然发现Microsoft Office PowerPoint可以被看作是一个压缩包，然后通过WinRAR解压出来一组XML文件。解压出来的文件包括：
一个索引文件名称为：[Content_Types].xml,
一个名为ppt的文件夹，在其内有两个重要的子文件夹：slides 和notesSlides
其中, [Content_Types].xml记录了每一张Slide的相对路径，每一个Slide note的相对路径。其内容如下图：
我们发现PPT中的所有内容都被记录在XML的<a:t></a:t>节点中， 所以，我们通过把所有a:t节点的内容导出，然后对内容进行修改，修改后再替换回原文件，这样将这一组文件进行压缩，生成了修改后的PowerPoint文件，该过程为PowerPoint的内容本地化提供了便捷途径。
这种做法相比较于调用Microsoft.Office.Interop.PowerPoint中的API的做法来说， 保留了原文的100%的格式，不需要后期PPT刷格式的操作。
以下是我们写的C#代码， 思路是将每张Slide的字符串导出到一个txt文件,通过trados翻译txt文件中的字符串，然后将修改后内容导入到PPT包内相应的XML文件中。
PPTZIPCommon
class PPTZIPCommon
{
/// <summary>
/// read file [Content_Types].xml
/// </summary>
/// <param name="root"></param>
/// <param name="SlideFiles">return slides </param>
/// <param name="NotesFiles">return slide notes</param>
internal static void ReadContentTypes(string root, ref List<string> SlideFiles, ref List<string> NotesFiles)
{
string ct_file = @"[Content_Types].xml";
string ct_fullName = Path.Combine(root, ct_file); if (!File.Exists(ct_fullName))
{
MessageBox.Show(string.Format("the [Content_Types].xml not exist in {0}", root));
return;
}
XmlDocument xml_doc = new XmlDocument();
xml_doc.Load(ct_fullName);
XmlElement rootElement = xml_doc.DocumentElement;
string slide_types = "application/vnd.openxmlformats-officedocument.presentationml.slide+xml";
string notes_types = "application/vnd.openxmlformats-officedocument.presentationml.notesSlide+xml"; XmlNodeList nodes = rootElement.ChildNodes;
foreach (XmlElement node in nodes)
{
if (node.Attributes["ContentType"].Value == slide_types)
{
string relatedPath = node.Attributes["PartName"].Value.Remove(, ).Replace(@"/", @"\");
string file = Path.Combine(root, relatedPath);
SlideFiles.Add(file);
}
else if (node.Attributes["ContentType"].Value == notes_types)
{
string relatedPath = node.Attributes["PartName"].Value.Remove(, ).Replace(@"/", @"\");
string file = Path.Combine(root, relatedPath);
NotesFiles.Add(file);
}
}
} internal static string GetPPTNameFromFullPath(string scanFolder)
{
int lastIndexOfSlash = scanFolder.LastIndexOf(@"\");
if (lastIndexOfSlash == scanFolder.Length - )
{
scanFolder = scanFolder.Remove(lastIndexOfSlash);
} string lastString = scanFolder.Substring(scanFolder.LastIndexOf(@"\") + );
string[] names = lastString.Split(new string[] { "." }, StringSplitOptions.RemoveEmptyEntries);
return names[];
}
}
PPTZIP
class PPTZIP
{
private static List<string> SlideFiles = new List<string>();
private static List<string> NotesFiles = new List<string>(); /// <summary>
/// collect together all the <a:t>...</a:t> strings, put it in txt file
/// txt file be saved to output\<original PPT name>_<fileName>.txt
/// </summary>
/// <param name="file">xml file that contains <a:t>...</a:t></param>
/// <param name="output">the txt file be saved to the output folder</param>
/// <param name="pptName">original PowerPoint file name</param>
private static void ReadATContent2TXT(string file, string output, string pptName)
{
StringBuilder sb = new StringBuilder();
using (StreamReader reader = new StreamReader(file))
{
string content = reader.ReadToEnd();
string pattern = @"<a:t>.[^<>]+</a:t>";
MatchCollection mc = Regex.Matches(content, pattern); for (int i = ; i < mc.Count; i++)
{
sb.AppendLine(string.Format("{0}^", mc[i].Value.Substring(, mc[i].Value.LastIndexOf("<") - )));
}
} FileInfo fi = new FileInfo(file);
string txtFile = Path.Combine(output, pptName+"_"+fi.Name + ".txt");
using (StreamWriter writer = new StreamWriter(txtFile))
{
writer.Write(sb.ToString().Trim());
writer.Flush();
writer.Close();
}
} public static void Export2TXTs(string scanFolder)
{
string ppt_name = PPTZIPCommon.GetPPTNameFromFullPath(scanFolder); PPTZIPCommon.ReadContentTypes(scanFolder, ref SlideFiles, ref NotesFiles); if (null != SlideFiles && SlideFiles.Count > )
{
foreach (var file in SlideFiles)
{
string outputfolder = Path.Combine(scanFolder, "SlideTXTs");
if (!Directory.Exists(outputfolder))
Directory.CreateDirectory(outputfolder);
string transFolder = Path.Combine(scanFolder, "SlideTXTs_Trans");
if (!Directory.Exists(transFolder))
Directory.CreateDirectory(transFolder); ReadATContent2TXT(file, outputfolder, ppt_name);
}
} if (null != NotesFiles && NotesFiles.Count > )
{
foreach (var file in NotesFiles)
{
string outputfolder = Path.Combine(scanFolder, "NotesTXTs");
if (!Directory.Exists(outputfolder))
Directory.CreateDirectory(outputfolder);
string transFolder = Path.Combine(scanFolder, "NotesTXTs_Trans");
if (!Directory.Exists(transFolder))
Directory.CreateDirectory(transFolder); ReadATContent2TXT(file, outputfolder,ppt_name);
} }
}
}
PPTZIPWriter
class PPTZIPWriter
{
private static List<string> SlideFiles = new List<string>();
private static List<string> NotesFiles = new List<string>(); private static void Replace(string file, List<string> original, List<string> translated)
{
string content = string.Empty;
using (StreamReader reader = new StreamReader(file))
{
content = reader.ReadToEnd();
for (int i = ; i < original.Count; i++)
{
content = content.Replace(string.Format("<a:t>{0}</a:t>", original[i]), string.Format("<a:t>{0}</a:t>", translated[i]));
} reader.Close();
} using (StreamWriter writer = new StreamWriter(file))
{
writer.Write(content);
writer.Flush();
writer.Close();
} } public static void Import2PPT(string scanFolder, string lan)
{
string ppt_name = PPTZIPCommon.GetPPTNameFromFullPath(scanFolder); // fullfill the two lists: SlideFiles and NotesFiles
PPTZIPCommon.ReadContentTypes(scanFolder,ref SlideFiles, ref NotesFiles); string srcFolder = "SlideTXTs";
string trgFolder = "SlideTXTs_Trans"; string srcFullPath = Path.Combine(scanFolder, srcFolder);
string trgFullPath = Path.Combine(scanFolder, trgFolder);
foreach (var file in SlideFiles)
{
ReplaceATContent(file, srcFullPath, trgFullPath, ppt_name, lan);
} string srcFolderNotes = "NotesTXTs";
string trgFolderNotes = "NotesTXTs_Trans";
string srcFullPath_trans = Path.Combine(scanFolder, srcFolderNotes);
string trgFullPath_trans = Path.Combine(scanFolder, trgFolderNotes);
foreach (var file in NotesFiles)
{
ReplaceATContent(file, srcFullPath_trans, trgFullPath_trans, ppt_name, lan);
}
} private static void ReplaceATContent(string file, string srcFolder, string trgFolder, string pptName, string lan)
{
if (!(Directory.Exists(srcFolder) && Directory.Exists(trgFolder)))
{
MessageBox.Show("SlideTXTs/NotesTXTs or SlideTXTs_Trans/NotesTXTs_Trans not exist");
return;
} FileInfo fi = new FileInfo(file);
string srcFileName = string.Format("{0}_{1}.txt",pptName,fi.Name);
string srcFileFullPath = Path.Combine(srcFolder, srcFileName); string trgFileName= string.Empty;
if(lan==string.Empty)
trgFileName = string.Format("{0}_{1}.txt", pptName, fi.Name);
else
trgFileName = string.Format("{0}_{1}_{2}.txt",pptName, fi.Name,lan);
string trgFileFullPath = Path.Combine(trgFolder, trgFileName); if (!(File.Exists(srcFileFullPath) && File.Exists(trgFileFullPath)))
{
MessageBox.Show(string.Format(@"File {0} not replaced",file));
return;
} List<string> originalString = new List<string>();
using (StreamReader reader = new StreamReader(srcFileFullPath))
{
string content = reader.ReadToEnd().Trim();
string[] strings = content.Split(new string[] { "^" }, StringSplitOptions.RemoveEmptyEntries);
for (int i = ; i < strings.Length; i++)
{
originalString.Add(strings[i].Contains("\r\n") ? strings[i].Remove(, ) : strings[i]);
}
} List<string> translatedString = new List<string>();
using (StreamReader reader = new StreamReader(trgFileFullPath))
{
string content = reader.ReadToEnd().Trim();
string[] strings = content.Split(new string[] { "^" }, StringSplitOptions.RemoveEmptyEntries);
for (int i = ; i < strings.Length; i++)
{
translatedString.Add(strings[i].Contains("\r\n") ? strings[i].Remove(, ) : strings[i]);
}
} if (originalString.Count != translatedString.Count)
{
MessageBox.Show(string.Format(@"translation string count not match:{0}",file));
return;
} Replace(file, originalString, translatedString);
}
}