nmp安装NPOI
读取Excel为DataTable
1 public static DataTable DoSql(string url) 2 { 3 try 4 { 5 //实例化DataTable来存放数据 6 DataTable dt = new DataTable(); 7 //string fileName = "MyData.xlsx"; 8 string fileName = url; 9 string sheetName = "sheet1";//Excel的工作表名称 10 bool isColumnName = true;//判断第一行是否为标题列 11 IWorkbook workbook;//创建一个工作薄接口 12 string fileExt = Path.GetExtension(fileName).ToLower();//获取文件的拓展名 13 //创建一个文件流 14 using (FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read)) 15 { 16 if (fileExt.ToLower() == ".xlsx") 17 { 18 workbook = new XSSFWorkbook(fs); 19 } 20 else 21 { 22 workbook = new HSSFWorkbook(fs); ; 23 } 24 25 //实例化sheet 26 ISheet sheet = null; 27 if (sheetName != null && sheetName != "")//判断是否存在sheet 28 { 29 sheet = workbook.GetSheet(sheetName); 30 if (sheet == null) 31 { 32 sheet = workbook.GetSheetAt(0);//从第一个开始读取，0位索引 33 } 34 else 35 { 36 sheet = workbook.GetSheetAt(0); 37 } 38 } 39 40 //获取表头 41 IRow header = sheet.GetRow(sheet.FirstRowNum); 42 int startRow = 0;//数据的第一行索引 43 if (isColumnName)//表示第一行是列名 44 { 45 startRow = sheet.FirstRowNum + 1;//数据从第二行开始读 46 47 //遍历表的第一行，即所有的列名 48 for (int i = header.FirstCellNum; i < header.LastCellNum; i++) 49 { 50 ICell cell = header.GetCell(i); 51 if (cell != null) 52 { 53 //获取列名的值 54 string cellValue = cell.ToString(); 55 if (cellValue != null) 56 { 57 DataColumn col = new DataColumn(cellValue); 58 dt.Columns.Add(col); 59 } 60 else 61 { 62 DataColumn col = new DataColumn(); 63 dt.Columns.Add(col); 64 } 65 } 66 } 67 } 68 69 //读取数据 70 for (int i = startRow; i <= sheet.LastRowNum; i++) 71 { 72 IRow row = sheet.GetRow(i); 73 if (row == null) 74 { 75 continue; 76 } 77 DataRow dr = dt.NewRow(); 78 for (int j = row.FirstCellNum; j < row.LastCellNum; j++) 79 { 80 if (row.GetCell(j) != null) 81 { 82 dr[j] = row.GetCell(j).ToString(); 83 } 84 85 } 86 dt.Rows.Add(dr); 87 } 88 89 } 90 return dt; 91 } 92 catch (Exception) 93 { 94 MessageBox.Show("打开失败，去找开发的"); 95 return null; 96 } 97 98 99 }
保存DataTable为Excel
public static bool DataTableToExcel(DataTable dt,string url) { string filepath = url; bool result = false; IWorkbook workbook = null; FileStream fs = null; IRow row = null; ISheet sheet = null; ICell cell = null; try { if (dt != null && dt.Rows.Count > 0) { workbook = new HSSFWorkbook(); sheet = workbook.CreateSheet("Sheet0");//创建一个名称为Sheet0的表 int rowCount = dt.Rows.Count;//行数 int columnCount = dt.Columns.Count;//列数 int cellnum; //设置列头 row = sheet.CreateRow(0);//excel第一行设为列头 for (int c = 0; c < columnCount; c++) { cell = row.CreateCell(c); cell.SetCellValue(dt.Columns[c].ColumnName); } //设置每行每列的单元格, for (int i = 0; i < rowCount; i++) { row = sheet.CreateRow(i + 1); for (int j = 0; j < columnCount; j++) { cell = row.CreateCell(j);//excel第二行开始写入数据 //cell.SetCellValue(dt.Rows[i][j].ToString()); //保存单元格格式为数字 if (j < 2) { cell.SetCellValue(dt.Rows[i][j].ToString()); } else { //cell.SetCellValue(int.Parse(dt.Rows[i][j].ToString())); if (dt.Rows[i][j] is DBNull) { cell.SetCellValue(dt.Rows[i][j].ToString()); } else { cellnum = Convert.ToInt32(dt.Rows[i][j].ToString()); cell.SetCellValue(cellnum); } } } } if (System.IO.File.Exists(filepath)) { File.Delete(filepath); //if (MessageBox.Show("该文件已存在！确定覆盖吗？", "WARNING", MessageBoxButtons.OKCancel) == DialogResult.OK) //{ // File.Delete(filepath); //} //else //{ // return false; //} } using (fs = File.OpenWrite(filepath)) { workbook.Write(fs);//向打开的这个xls文件中写入数据 result = true; } } return result; } catch (Exception ex) { MessageBox.Show(ex.Message); if (fs != null) { fs.Close(); } return false; } }