NPOI导出excel

 private void btnadd_MouseUp(object sender, MouseButtonEventArgs e)
        {
            try
            {
                #region 打印导出统计数据
                if (dt != null && dt.Rows.Count > 0)
                {
                    //创建工作薄
                    HSSFWorkbook wb = new HSSFWorkbook();
                    //创建一个名称为mySheet的表
                    ISheet sh = wb.CreateSheet("mySheet");
                    #region  设置表格内容
                    SetTJRow(wb, sh);//设置表头
                    for (int i = 0; i < dt.Rows.Count; i++)
                    {
                        IRow row = sh.CreateRow(i + 1);
                        for (int j = 3; j < dt.Columns.Count; j++)
                        {
                            string content = dt.Rows[i][j].ToString();
                            if (j == 3)
                            {
                                ICell cell = row.CreateCell(j - 3);
                                cell.SetCellValue(content);
                            }
                            else if (j > 4)
                            {
                                if (dt.Rows[i][j - 2].ToString().Contains("小计"))
                                {
                                    ICell cell = row.CreateCell(j - 4);
                                    cell.SetCellValue("总人数:" + dt.Rows[i][j - 1].ToString());
                                }
                                else if (dt.Rows[i][j - 2].ToString().Contains("总计"))
                                {
                                    ICell cell = row.CreateCell(j - 4);
                                    cell.SetCellValue("总人数:" + dt.Rows[i][j - 1].ToString());
                                }
                                else
                                {
                                    ICell cell = row.CreateCell(j - 4);
                                    cell.SetCellValue(content);
                                }
                            }
                        }
                    }
                    string saveFileName = "人员工资统计表.xls";
                    //FileStream fs=new FileStream();
                    SaveFileDialog saveDialog = new SaveFileDialog();
                    saveDialog.DefaultExt = "xls";
                    saveDialog.Filter = "Excel文件|*.xls";
                    saveDialog.FileName = saveFileName;
                    saveDialog.ShowDialog();
                    saveFileName = saveDialog.FileName;
                    if (saveFileName.IndexOf(":") < 0) return; //被点了取消
                    if (saveFileName != "")
                    {
                        using (FileStream fs = File.OpenWrite(saveDialog.FileName))//打开一个xls文件，如果没有则自行创建，如果存在myxls.xls文件则在创建是不要打开该文件
                        {
                            try
                            {
                                wb.Write(fs);
                                MessageBox.Show("导出成功！", "提示", MessageBoxButton.OK, MessageBoxImage.Asterisk);
                            }
                            catch (Exception ex)
                            {
                                MessageBox.Show("导出文件时出错,文件可能正被打开！\n" + ex.Message, "提示", MessageBoxButton.OK, MessageBoxImage.Error);
                            }
                        }
                    }
                    else
                    {
                        MessageBox.Show("请选择数据源！");
                    }
                    #endregion
                }
                else
                {
                    MessageBox.Show("请选择数据源！");
                }
                #endregion
            }
            catch (Exception ex)
            { 
                MessageBox.Show(ex.Message, "提示", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

 1   #region 定义单元格常用到的样式
 2         static ICellStyle Getcellstyle(IWorkbook wb, stylexls str)
 3         {
 4             ICellStyle cellStyle = wb.CreateCellStyle();
 5 
 6             //定义几种字体  
 7             //也可以一种字体，写一些公共属性，然后在下面需要时加特殊的  
 8             IFont font12 = wb.CreateFont();
 9             font12.FontHeightInPoints = 10;
10             font12.FontName = "微软雅黑";
11 
12 
13             IFont font = wb.CreateFont();
14             font.FontName = "微软雅黑";
15             //font.Underline = 1;下划线  
16 
17 
18             IFont fontcolorblue = wb.CreateFont();
19             fontcolorblue.Color = HSSFColor.OliveGreen.Blue.Index;
20             fontcolorblue.IsItalic = true;//下划线  
21             fontcolorblue.FontName = "微软雅黑";
22 
23 
24             //边框  
25             cellStyle.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
26             cellStyle.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
27             cellStyle.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;
28             cellStyle.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
29             //水平对齐  
30             cellStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Left;
31 
32             //垂直对齐  
33             cellStyle.VerticalAlignment = NPOI.SS.UserModel.VerticalAlignment.Center;
34 
35             //自动换行  
36             cellStyle.WrapText = true;
37 
38             //缩进;当设置为1时，前面留的空白太大了。希旺官网改进。或者是我设置的不对  
39             cellStyle.Indention = 0;
40 
41             //上面基本都是设共公的设置  
42             //下面列出了常用的字段类型  
43             switch (str)
44             {
45                 case stylexls.头:
46                     // cellStyle.FillPattern = FillPatternType.LEAST_DOTS;  
47                     cellStyle.SetFont(font12);
48                     break;
49                 case stylexls.时间:
50                     IDataFormat datastyle = wb.CreateDataFormat();
51 
52                     cellStyle.DataFormat = datastyle.GetFormat("yyyy/mm/dd");
53                     cellStyle.SetFont(font);
54                     break;
55                 case stylexls.数字:
56                     cellStyle.DataFormat = HSSFDataFormat.GetBuiltinFormat("0.00");
57                     cellStyle.SetFont(font);
58                     break;
59                 case stylexls.钱:
60                     IDataFormat format = wb.CreateDataFormat();
61                     cellStyle.DataFormat = format.GetFormat("￥#,##0");
62                     cellStyle.SetFont(font);
63                     break;
64                 case stylexls.百分比:
65                     cellStyle.DataFormat = HSSFDataFormat.GetBuiltinFormat("0.00%");
66                     cellStyle.SetFont(font);
67                     break;
68                 case stylexls.中文大写:
69                     IDataFormat format1 = wb.CreateDataFormat();
70                     cellStyle.DataFormat = format1.GetFormat("[DbNum2][$-804]0");
71                     cellStyle.SetFont(font);
72                     break;
73                 case stylexls.科学计数法:
74                     cellStyle.DataFormat = HSSFDataFormat.GetBuiltinFormat("0.00E+00");
75                     cellStyle.SetFont(font);
76                     break;
77                 case stylexls.默认:
78                     cellStyle.SetFont(font);
79                     break;
80             }
81             return cellStyle;
82 
83 
84         }
85         #endregion