public void AddFontSubstitutes()
{
FontSettings fontSettings = new FontSettings();
fontSettings.SetFontSubstitutes("Slab", new string[] { "Times New Roman", "Arial" });
fontSettings.AddFontSubstitutes("Arvo", new string[] { "Open Sans", "Arial" });
Document doc = new Document(MyDir + "Rendering.doc");
doc.FontSettings = fontSettings;
MemoryStream dstStream = new MemoryStream();
doc.Save(dstStream, SaveFormat.Docx);
string[] alternativeFonts = doc.FontSettings.GetFontSubstitutes("Slab");
Assert.AreEqual(new string[] { "Times New Roman", "Arial" }, alternativeFonts);
alternativeFonts = doc.FontSettings.GetFontSubstitutes("Arvo");
Assert.AreEqual(new string[] { "Open Sans", "Arial" }, alternativeFonts);
}