aspose.word 查找文本并加下划线

 private Run SplitRun(Run run, int position)
 {
            Run beforeRun = (Run)run.Clone(true);
            beforeRun.Text = run.Text.Substring(0, position);
            beforeRun.Font.Underline = Underline.Single;
            run.Text = run.Text.Substring(position);
            run.ParentNode.InsertBefore(beforeRun, run);

            return run;
  }