This is easy:
COM Microsoft Word 11.0 ( Microsoft.Office.Interop.Word). , Visual Studio Tools Office System / Interop, VS.NET Office , .
Word.Application var app = new Word.Application()
var doc = app.Documents.Open(...). , # 3.5 . , System.Reflection.Missing.Value .
doc.Fields foreach: .Code, .Result .
:
foreach(Field f in doc.Fields)
if(f.Code.Text.Contains("lastName"))
f.Result.Text = this.LastName;
...
, DependencyProperty "LastName", XAML :
<TextBox Text="{Binding LastName}" />