using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Wordprocessing;
 
namespace AddStringToWord
{
  public class Program
  {
    public static void Main(string[] args)
    {
      AddString("Test.docx", "你好呀");
    }
 
    public static void AddString(string filePath, string str)
    {
      using (WordprocessingDocument doc = WordprocessingDocument.Open(filePath, true))
      {
        Paragraph paragraph = new Paragraph();
        Run run = new Run();
 
        RunProperties runProperties = new RunProperties(); //属性
 
        RunFonts fonts = new RunFonts() { EastAsia = "DFKai-SB" }; // 设置字体
        FontSize size = new FontSize() { Val = "52" }; // 设置字体大小
        Color color = new Color() { Val = "red" }; // 设置字体样式
 
        // 将样式添加到属性里面
        runProperties.Append(color);
        runProperties.Append(size);
        runProperties.Append(fonts);
 
        run.Append(runProperties);
        run.Append(new Text(str));
        paragraph.Append(run);
        doc.MainDocumentPart.Document.Body.Append(paragraph);
        doc.MainDocumentPart.Document.Save();
      }
    }
  }
}