Free Spire.Doc for .NET
Visual Studio
1.通过官网（https://www.e-iceblue.cn/Introduce/Free-Spire-Doc-NET.html）下载安装包--解压-安装。在程序中添加引用Spire.doc.dll，dll文件在安装路径下的bin文件夹中。2.通过Nuget官网下载。（http://www.nuget.org/packages/FreeSpire.Doc/）添加引用完成后，如下图：
using Spire.Doc;using Spire.Doc.Documents;using Spire.Doc.Fields;namespace InsertBookmark2_Doc{ class Program { static void Main(string[] args) { //创建Document类的对象，并加载测试文档 Document document = new Document(); document.LoadFromFile('test.docx'); //查找需要设置书签的内容 TextSelection selection = document.FindString('ALC', false, false); TextRange range = selection.GetAsOneRange(); Paragraph para = range.OwnerParagraph; string text = range.Text; int index = para.ChildObjects.IndexOf(range); //添加书签，并命名 BookmarkStart start = new BookmarkStart(document,'书签1'); BookmarkEnd end = new BookmarkEnd(document, '书签1'); para.ChildObjects.Insert(index, start); para.ChildObjects.Insert(index + 2, end); BookmarksNavigator navigator = new BookmarksNavigator(document); navigator.MoveToBookmark('书签1'); //保存文档 document.SaveToFile('Bookmark.docx', FileFormat.Docx); System.Diagnostics.Process.Start('Bookmark.docx'); } }}
书签添加效果，如下图：