Basic support for embedding RTF & HTML & More (AddEmbeddedDocument)

[PrzemyslawKlys]

This PR implements embedding files of a particular type displayed as regular content in Word.

• [x] embedding of HTML document into Word document.AddEmbeddedDocument(file);
• [x] embedding of RTF document into Word document.AddEmbeddedDocument(file);
• [x] embedding of TEXT document into Word document.AddEmbeddedDocument(file);
• [x] Find embedded documents in Word, document.EmbeddedDocuments list
• [x] Save embedded document back to file document.EmbeddedDocuments[0].Save("C:\\TEMP\\EmbeddedFileHTML.html");

Example 1:

public static void Example_EmbedFileMultiple(string folderPath, string templateFolder, bool openWord) {
    Console.WriteLine("[*] Creating standard document with multiple files embedded");
    string filePath = System.IO.Path.Combine(folderPath, "MultipleFilesEmedded.docx");

    string htmlFilePath = System.IO.Path.Combine(templateFolder, "SampleFileHTML.html");
    string rtfFilePath = System.IO.Path.Combine(templateFolder, "SampleFileRTF.rtf");
    string txtFilePath = System.IO.Path.Combine(templateFolder, "SampleFileTEXT.txt");

    using (WordDocument document = WordDocument.Create(filePath)) {
        document.AddParagraph("Add RTF document in front of the document");
        // we natively support HTML by using extension to decide what it is
        document.AddEmbeddedDocument(rtfFilePath);

        document.AddPageBreak();

        document.AddParagraph("Add HTML");

        // we natively support HTML by using extension to decide what it is
        document.AddEmbeddedDocument(htmlFilePath);

        document.AddPageBreak();

        document.AddParagraph("Add TEXT 1");

        // we natively support TextPlain by using extension (log/txt) to apply text/plain content type
        document.AddEmbeddedDocument(txtFilePath);

        document.AddPageBreak();

        document.AddParagraph("Add TEXT 2");

        // but you can specify type as you want, if the extension would be .ext, and the content type would be text/plain
        document.AddEmbeddedDocument(txtFilePath, AlternativeFormatImportPartType.TextPlain);

        Console.WriteLine("Embedded documents in word: " + document.EmbeddedDocuments.Count);
        Console.WriteLine("Embedded documents in Section 0: " + document.Sections[0].EmbeddedDocuments.Count);
        Console.WriteLine("Content type 0: " + document.EmbeddedDocuments[0].ContentType);
        Console.WriteLine("Content type 1: " + document.EmbeddedDocuments[1].ContentType);

        document.AddPageBreak();

        document.AddParagraph("Add RTF 2");

        document.AddEmbeddedDocument(rtfFilePath);

        Console.WriteLine("Content type 0: " + document.EmbeddedDocuments[0].ContentType);
        Console.WriteLine("Content type 1: " + document.EmbeddedDocuments[1].ContentType);
        Console.WriteLine("Content type 2: " + document.EmbeddedDocuments[2].ContentType);
        Console.WriteLine("Content type 3: " + document.EmbeddedDocuments[3].ContentType);
        Console.WriteLine("Content type 4: " + document.EmbeddedDocuments[4].ContentType);

        Console.WriteLine("Embedded documents in word: " + document.EmbeddedDocuments.Count);

        document.Save(openWord);
    }
}

Example for saving:

public static void Example_EmbedFileHTML(string folderPath, string templateFolder, bool openWord) {
    Console.WriteLine("[*] Creating standard document with embedded HTML file");
    string filePath = System.IO.Path.Combine(folderPath, "EmbeddedFileHTML.docx");
    string htmlFilePath = System.IO.Path.Combine(templateFolder, "SampleFileHTML.html");
    using (WordDocument document = WordDocument.Create(filePath)) {
        Console.WriteLine("Embedded documents in word: " + document.EmbeddedDocuments.Count);
        Console.WriteLine("Embedded documents in Section 0: " + document.Sections[0].EmbeddedDocuments.Count);

        document.AddParagraph("Add HTML document in DOCX");

        document.AddSection();

        Console.WriteLine("Embedded documents in Section 1: " + document.Sections[1].EmbeddedDocuments.Count);

        document.AddEmbeddedDocument(htmlFilePath);

        document.EmbeddedDocuments[0].Save("C:\\TEMP\\EmbeddedFileHTML.html");

        Console.WriteLine("Embedded documents in word: " + document.EmbeddedDocuments.Count);
        Console.WriteLine("Embedded documents in Section 0: " + document.Sections[0].EmbeddedDocuments.Count);
        Console.WriteLine("Embedded documents in Section 1: " + document.Sections[1].EmbeddedDocuments.Count);
        Console.WriteLine("Content type: " + document.EmbeddedDocuments[0].ContentType);

        document.Save(openWord);
    }
}