【原创】WinForm操作EXCEL（第三方插件NPOI）

根据上一章的 WinForm导出数据到EXCEL（根据微软的Excel插件） 中说了一些问题，通过微软的Excel插件来导入到Excel，不过在布置时发现服务器必须安装office组件才可以应用，好像并不方便，于是想到不用微软的Excel插件实现上一章的功能，该如何实现呢？

今天我就用第三方插件NPOI来实现其功能

（1）插件的下载

可以到正式官网去上载，我这里给出这些组件[NPOI组件下载]

（2）命名空间引用

using NPOI;
using NPOI.HPSF;
using NPOI.HSSF;
using NPOI.HSSF.UserModel;
using NPOI.HSSF.Util;
using NPOI.POIFS;
using NPOI.Util;

（3）代码实现

   /// <summary>
        /// 导出Excel文件
        /// </summary>
        /// <param name="dt">要导入到Excel的数据</param>
        public static string DataTableToExcel(System.Data.DataTable dt)
        {
            string msg = "";
            string strFilePath = System.AppDomain.CurrentDomain.BaseDirectory + DateTime.Now.ToString("yyyyMMddhhmmss") + ".xls";
            HSSFWorkbook workbook = new HSSFWorkbook();
            try
            {
                int MaxRowCount = 60000;


                int rowCount = dt.Rows.Count;
                int colCount = dt.Columns.Count;


                if (rowCount > 0 && rowCount <= MaxRowCount)
                {
                    HSSFSheet sheet = workbook.CreateSheet("总信息");

                    HSSFRow dataRowColumn = sheet.CreateRow(0);
                    for (int j = 0; j < colCount; j++)
                    {
                        HSSFCell newCell = dataRowColumn.CreateCell(j);
                        newCell.SetCellValue(dt.Columns[j].ColumnName.ToString());
                    }

                    for (int j = 0; j < rowCount; j++)
                    {
                        HSSFRow dataRow = sheet.CreateRow(j + 1);
                        for (int k = 0; k < colCount; k++)
                        {
                            HSSFCell newCell = dataRow.CreateCell(k);
                            newCell.SetCellValue(dt.Rows[j][k].ToString());
                        }
                    }
                }
                else //超过sheet表单的就再创适sheet表单
                {
                    int sheetCount = 1; //sheet表单个数
                    if (rowCount % MaxRowCount == 0)
                    {
                        sheetCount = rowCount / MaxRowCount;
                    }
                    else
                    {
                        sheetCount = rowCount / MaxRowCount + 1;
                    }

                    int Flag = 1;
                    for (var m = 0; m < sheetCount; m++)
                    {
              
                        HSSFSheet sheet = workbook.CreateSheet("第" + (m + 1) + "页数据");

                 
                        if (Flag == sheetCount && (rowCount % MaxRowCount != 0))
                        {
                            int newrowCount = rowCount - ((Flag - 1) * MaxRowCount); 


                            int RowIndex = 0;

                            HSSFRow dataRowColumn = sheet.CreateRow(0);
                            for (int j = 0; j < colCount; j++)
                            {
                                HSSFCell newCell = dataRowColumn.CreateCell(j);
                                newCell.SetCellValue(dt.Columns[j].ColumnName.ToString());
                            }



                            int startIndex = (Flag - 1) * MaxRowCount;
                            for (int n = startIndex; n < startIndex + newrowCount; n++)
                            {
                                HSSFRow dataRow = sheet.CreateRow(RowIndex + 1);
                                for (int t = 0; t < colCount; t++)
                                {
                                    HSSFCell newCell = dataRow.CreateCell(t);
                                    newCell.SetCellValue(dt.Rows[n][t].ToString());
                                }
                                                              

                                RowIndex++;
                            }

                        }
                        else
                        {
                            HSSFRow dataRowColumn = sheet.CreateRow(0);
                            for (int j = 0; j < colCount; j++)
                            {
                                HSSFCell newCell = dataRowColumn.CreateCell(j);
                                newCell.SetCellValue(dt.Columns[j].ColumnName.ToString());
                            }
                            int startIndex = (Flag - 1) * MaxRowCount;
                            int rowIndex = 0;
                            for (int n = startIndex; n < startIndex + MaxRowCount; n++)
                            {
                                HSSFRow dataRow = sheet.CreateRow(rowIndex + 1);
                                for (int t = 0; t < colCount; t++)
                                {
                                    HSSFCell newCell = dataRow.CreateCell(t);
                                    newCell.SetCellValue(dt.Rows[n][t].ToString());
                                }
                                rowIndex++;
                            }

                        }
                        Flag++;
                    }

                }
                FileStream file = new FileStream(strFilePath, FileMode.Create);
                workbook.Write(file);
                msg = "生成成功：请到文件" + strFilePath + "下取得该文件";
                file.Close();         

            }
            catch
            {
                workbook.Dispose();
                GC.Collect();
                return "出现异常";
            }
            finally
            {

                workbook.Dispose();
                GC.Collect();
            }

            return msg;
        }

代码完毕。

关于NPOI的相关知识我不再赘述，网上一大堆。我这里只是简单的用一些它的小知识点。

 转载的请注原创地址，谢谢。