PM> Install-Package Spire.Doc

using Spire.Doc;
using Spire.Doc.Documents;
using System;

namespace RemoveEmptyLines
{
    class Program
    {

        static void Main(string[] args)
        {

            //創(chuàng)建 Document 實例
            Document doc = new Document();

            //加載示例 Word 文檔
            doc.LoadFromFile(@"D:\Files\input.docx");

            //遍歷文檔中的所有段落
            foreach (Section section in doc.Sections)
            {
                for (int i = 0; i < section.Body.ChildObjects.Count; i++)
                {
                    if (section.Body.ChildObjects[i].DocumentObjectType == DocumentObjectType.Paragraph)
                    {
                        //判斷該段落是否為空白段落
                        if (String.IsNullOrEmpty((section.Body.ChildObjects[i] as Paragraph).Text.Trim()))
                        {
                            //刪除空白段落
                            section.Body.ChildObjects.Remove(section.Body.ChildObjects[i]);
                            i--;
                        }
                    }

                }
            }

            //保存文檔
            doc.SaveToFile("RemoveEmptyLines.docx", FileFormat.Docx2013);

        }

    }
}