.NetCore 导出Execl

/* 

Nuget  - NPOI.2.5.1

*/

using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System; 
using System.Data;
using System.IO;

//-----------------------------------------------------------------
///dt 数据列表
///sheetName 标签名
///excelpath 保存路径 例：C:/WORK/XXXX.xls
 public static void ExportExcel(DataTable dt, string sheetName, string excelpath)
        {
            try
            {
                IWorkbook workbook;
                if (excelpath.Contains(".xlsx"))
                    workbook = new XSSFWorkbook();
                else if (excelpath.Contains(".xls"))
                    workbook = new HSSFWorkbook();
                else
                    workbook = null; 
                ISheet sheet = null;     
                int headRowIndex = 0;           
                if (!string.IsNullOrEmpty(dt.TableName))
                {
                    sheetName = dt.TableName;
                }
                sheet = workbook.CreateSheet(sheetName);
                int rowIndex = 0;


                #region 列头及样式
                {
                    IRow headerRow = sheet.CreateRow(headRowIndex);

                    ICellStyle headStyle = workbook.CreateCellStyle();
                    headStyle.Alignment = HorizontalAlignment.Center;
                    IFont font = workbook.CreateFont();
                    font.FontHeightInPoints = 10;
                    font.Boldweight = 700;
                    headStyle.SetFont(font);

                    foreach (DataColumn column in dt.Columns)
                    {
                        headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
                        headerRow.GetCell(column.Ordinal).CellStyle = headStyle;
                    }
                }
                #endregion

                #region 填充内容

                foreach (DataRow row in dt.Rows)
                {
                    rowIndex++;
                    IRow dataRow = sheet.CreateRow(rowIndex);
                    foreach (DataColumn column in dt.Columns)
                    {
                        string drValue = row[column].ToString();
                        dataRow.CreateCell(column.Ordinal).SetCellValue(drValue);
                    }
                }
                #endregion       
                
                using (FileStream file = new FileStream(excelpath, FileMode.Create))
                {
                    workbook.Write(file);
                }
                return;
            }

            catch (Exception ex)
            {
                 //log4.logtofile('ImportExcel',ex.Message);
            }

        }