.net中数据集合导出为Excel（支持泛型及显示字段顺序，可自定义显示列名）

  public class DataExportHelper
    {     
        /// <summary>
        /// 导出EXCEL
        /// </summary>
        /// <typeparam name="T">集合类型</typeparam>
        /// <param name="data">数据集合</param>
        /// <param name="exportFileName">要显示的列名(类字段名)</param>
        /// <param name="columnNames"></param>
        public static void ExcelExport<T>(List<T> data, string exportFileName, List<string> columnNames)
        {
            StringWriter sw = GetStringWriter(data,columnNames);
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
            string fileName = exportFileName;
            //判断浏览器如果是IE则对文件名进行URL编码处理
            string ua = HttpContext.Current.Request.UserAgent;
            if (!string.IsNullOrEmpty(ua))
            {
                if (ua.ToLower().IndexOf("msie", System.StringComparison.Ordinal)>=0)
                {
                    fileName = HttpUtility.UrlEncode(exportFileName, Encoding.UTF8);
                }
            }

            
            string str = "attachment;filename= " + fileName + ".xls ";
            HttpContext.Current.Response.AppendHeader("Content-Disposition", str);
            HttpContext.Current.Response.ContentType = "application/ms-excel";
            HttpContext.Current.Response.Write(sw);
            HttpContext.Current.Response.End();
        }

        /// <summary>
        /// 数据字串拼接  
        /// </summary>
        /// <typeparam name="T">集合类型</typeparam>
        /// <param name="data">数据集合</param>
        /// <param name="columnNames">要显示的列名(类字段名)</param>
        /// <returns></returns>
        public static StringWriter GetStringWriter<T>(List<T> data,List<string> columnNames )
        {
            StringWriter sw = new StringWriter();

            var type = typeof(T);
            var properties = type.GetProperties();
            if (columnNames!=null&&columnNames.Count > 0)
            {
               // properties = properties.Where(t => columnNames.Contains(t.Name)).ToArray();
                //为了与指定字段顺序一致，才如此循环
                PropertyInfo[] property=new PropertyInfo[columnNames.Count];
                for (int i = 0; i < columnNames.Count; i++)
                {
                    property[i] = properties.FirstOrDefault(t => t.Name == columnNames[i]);
                }
                properties = property;
            }
            sw.Write(sw.NewLine);
            if (data != null)
            {
                //添加列名：
                var colName = "";
                foreach (var property in properties)
                {
                    colName = property.Name;
                    if (property.CustomAttributes.LongCount() >0)
                    {
                       colName = property.CustomAttributes.First().ConstructorArguments.First().Value.ToString();
                    }
                    sw.Write(colName + "\t");
                }
                sw.Write(sw.NewLine);

                foreach (var row in data)
                {
                    foreach (var property in properties)
                        sw.Write(property.GetValue(row, null) + "\t");

                    sw.Write(sw.NewLine);
                }
            }
            sw.Close();
            return sw;
        }
 
    }

      protected void CreateExecl(int classId)
        {
            StudentManager marager = new StudentManager();
            List<StudentModel> list = marager.StudentList(classId);
            string fileName = "XX班学生数据";
            var listfiled = new List<string>
            {
                "Id",
                "Name",
                "Birthday"
            };
            DataExportHelper.ExcelExport(list, fileName, listfiled);
        }

public class StudentModel
    {
        [Description("学号")]
        public DateTime Id { get; set; }

        [Description("姓名")]
        public double Name { get; set; }

         [Description("生日")]
        public double Birthday { get; set; }
    }