如何使用OpenXML SDK在Powerpoint幻灯片中隐藏文本？

using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Presentation;
using A = DocumentFormat.OpenXml.Drawing;
using P = DocumentFormat.OpenXml.Presentation;
using D = DocumentFormat.OpenXml.Drawing;
using System.Linq;

public void HideTextInPowerPointSlide(string filePath)
{
    // 打开PowerPoint文档
    using (PresentationDocument presentationDocument = PresentationDocument.Open(filePath, true))
    {
        // 获取PresentationPart对象
        PresentationPart presentationPart = presentationDocument.PresentationPart;

        // 获取Presentation对象
        Presentation presentation = presentationPart.Presentation;

        // 获取幻灯片集合
        SlidePart[] slideParts = presentationPart.SlideParts.ToArray();

        // 遍历幻灯片集合
        foreach (SlidePart slidePart in slideParts)
        {
            // 获取Slide对象
            Slide slide = slidePart.Slide;

            // 获取文本框集合
            IEnumerable<DocumentFormat.OpenXml.Presentation.TextBody> textBodies = slide.Descendants<DocumentFormat.OpenXml.Presentation.TextBody>();

            foreach (DocumentFormat.OpenXml.Presentation.TextBody textBody in textBodies)
            {
                // 隐藏文本
                textBody.Elements<DocumentFormat.OpenXml.Drawing.TextBody>().First().Elements<D.Paragraph>().First().Elements<D.Run>().First().RunProperties.Append(new A.NoFill());

                //保存对文档的修改
                slidePart.Slide.Save();
            }
        }

        //保存并关闭PowerPoint文档
        presentationDocument.Save();
    }
}