效果如下:

建议在保存时指定编码为UTF-8：

using (StreamWriter sw = new StreamWriter(filePath, false, Encoding.UTF8))

     {

         // 写入内容

     }

最终

using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Runtime;
using System;
using System.ComponentModel;
using System.Diagnostics;
using System.IO;
using System.Text;
using Path = System.IO.Path;
namespace EnhancedEntityPropertyExporter
{public class ExportCommands{[CommandMethod("xx")]public void 属性查询(){List<Entity> ents = SelectEntities<Entity>();if (ents is null || ents.Count == 0){Application.DocumentManager.MdiActiveDocument.Editor.WriteMessage("未选择!\n");return;}try{// 获取桌面路径string desktopPath = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory);// 生成基础文件名（格式：图元属性20231010）string baseFileName = $"图元属性{DateTime.Now:yyyyMMddhhmmss}";string fullPath = "";int copyNumber = 0;// 生成唯一文件名do{string suffix = copyNumber > 0 ? $"复件{copyNumber}" : "";string fileName = $"{baseFileName}{suffix}.txt";fullPath = Path.Combine(desktopPath, fileName);copyNumber++;} while (File.Exists(fullPath)); // 循环直到找到不存在的文件名// 构建属性字符串using (StreamWriter sw = new StreamWriter(fullPath, false, System.Text.Encoding.UTF8)){foreach (var obj in ents){sw.WriteLine($"AutoCAD 实体属性导出 - {DateTime.Now}");sw.WriteLine("====================================");sw.WriteLine($"实体类型: {obj.GetType().Name}");sw.WriteLine($"句柄(Handle): {obj.Handle}");sw.WriteLine($"图层(Layer): {obj.Layer}");sw.WriteLine("====================================");sw.WriteLine();string str = "";str += "对象全部属性:  >\n";str += $"类型:    {obj.GetType()}\n";PropertyInfo[] pis = obj.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance);foreach (var pi in pis){try{var value = pi.GetValue(obj, null);str += $"{pi.Name} :    {(value != null ? value.ToString() : "Null")}\n";}catch{str += $"{pi.Name} :    获取失败\n";}}str += "\n";sw.Write(str); // 写入文件}}// 用记事本打开文件Process.Start("notepad.exe", fullPath);}catch (Exception ex){MessageBox.Show($"导出失败：{ex.Message}");}}public List<T> SelectEntities<T>() where T : Entity{List<T> result = new List<T>();Editor editor = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument.Editor;var pso = new PromptSelectionOptions();pso.MessageForAdding = "\n请选择：";PromptSelectionResult psr = editor.GetSelection(pso);if (psr.Status == PromptStatus.OK){ObjectId[] objectids = psr.Value.GetObjectIds();Database database = HostApplicationServices.WorkingDatabase;using (Transaction tran = database.TransactionManager.StartTransaction()){foreach (var item in objectids){Entity entity = item.GetObject(OpenMode.ForRead) as Entity;if (entity is T){result.Add(entity as T);}}}}return result;}}
}