NPOI导出excel表格应用

最近接到一个需求，在原有系统上做二次开发 ，要求导出DataGridView数据到Excel表格中。要求如下：

1. 兼容所有excel版本；
2. 导出后excel各列的样式，字段类型不变。

成型如下：

具体代码实现如下：

1. girdview数据绑定

        public Form1()

        {

            InitializeComponent();

            Load += Form1_Load;

        }

       

        /// <summary>

        /// 给DataGridView绑定数据

        /// </summary>

        /// <param name="sender"></param>

        /// <param name="e"></param>

        void Form1_Load(object sender, EventArgs e)

        {

            List<Jacket> lst = new List<Jacket>();

            for (int i = 0; i < 3; i++)

            {

                Jacket j = new Jacket();

                j.Type = "男款";

                j.Color = "black";

                j.Size = "S";

                j.price = 55.4M + i;

                lst.Add(j);

            }



            for (int i = 0; i < 2; i++)

            {

                Jacket j = new Jacket();

                j.Type = "男款";

                j.Color = "blue";

                j.Size = "L";

                j.price = 60.4M + i;

                lst.Add(j);

            }



            for (int i = 0; i < 4; i++)

            {

                Jacket j = new Jacket();

                j.Type = "女款";

                j.Color = "red";

                j.Size = "S";

                j.price = 60.4M + i;

                lst.Add(j);

            }



            dataGridView1.DataSource = lst;

        }

　　2.导出excel表格

　　　　 /// <summary>

        /// 导出操作

        /// </summary>

        /// <param name="sender"></param>

        /// <param name="e"></param>

        private void button1_Click(object sender, EventArgs e)

        {

            ExportExcel("d:\\1.xls", dataGridView1, "宋体", 8);

        }



        /// <summary>

        /// 导出excel

        /// </summary>

        /// <param name="fileName">导出路径</param>

        /// <param name="dgv">数据grilview</param>

        /// <param name="fontName">字体</param>

        /// <param name="fontSize">大小</param>

        void ExportExcel(string fileName, DataGridView dgv, string fontName, short fontSize)

        {

            //检测是否有数据

            //if (dgv.SelectedRows.Count == 0) return;

            //创建主要对象

            HSSFWorkbook workbook = new HSSFWorkbook();

            HSSFSheet sheet = (HSSFSheet)workbook.CreateSheet("Weight");

            //设置字体，大小，对齐方式

            HSSFCellStyle style = (HSSFCellStyle)workbook.CreateCellStyle();

            HSSFFont font = (HSSFFont)workbook.CreateFont();

            font.FontName = fontName;

            font.FontHeightInPoints = fontSize;

            style.SetFont(font);

            style.Alignment = NPOI.SS.UserModel.HorizontalAlignment.CENTER; //居中对齐

            //添加表头

            HSSFRow dataRow = (HSSFRow)sheet.CreateRow(0);

            for (int i = 0; i < dgv.Columns.Count; i++)

            {

                dataRow.CreateCell(i).SetCellValue(dgv.Columns[i].HeaderText);

                dataRow.GetCell(i).CellStyle = style;

            }

            //添加列及内容

            for (int i = 0; i < dgv.Rows.Count; i++)

            {

                dataRow = (HSSFRow)sheet.CreateRow(i + 1);

                for (int j = 0; j < dgv.Columns.Count; j++)

                {

                    string ValueType = dgv.Rows[i].Cells[j].Value.GetType().ToString();

                    string Value = dgv.Rows[i].Cells[j].Value.ToString();

                    switch (ValueType)

                    {

                        case "System.String"://字符串类型

                            dataRow.CreateCell(j).SetCellValue(Value);

                            break;

                        case "System.DateTime"://日期类型

                            System.DateTime dateV;

                            System.DateTime.TryParse(Value, out dateV);

                            dataRow.CreateCell(j).SetCellValue(dateV);

                            break;

                        case "System.Boolean"://布尔型

                            bool boolV = false;

                            bool.TryParse(Value, out boolV);

                            dataRow.CreateCell(j).SetCellValue(boolV);

                            break;

                        case "System.Int16"://整型

                        case "System.Int32":

                        case "System.Int64":

                        case "System.Byte":

                            int intV = 0;

                            int.TryParse(Value, out intV);

                            dataRow.CreateCell(j).SetCellValue(intV);

                            break;

                        case "System.Decimal"://浮点型

                        case "System.Double":

                            double doubV = 0;

                            double.TryParse(Value, out doubV);

                            dataRow.CreateCell(j).SetCellValue(doubV);

                            break;

                        case "System.DBNull"://空值处理

                            dataRow.CreateCell(j).SetCellValue("");

                            break;

                        default:

                            dataRow.CreateCell(j).SetCellValue("");

                            break;

                    }

                    dataRow.GetCell(j).CellStyle = style;

                    //设置宽度

                    sheet.SetColumnWidth(j, (Value.Length + 10) * 256);

                }

            }

            //保存文件

            string saveFileName = "";

            SaveFileDialog saveDialog = new SaveFileDialog();

            saveDialog.DefaultExt = "xls";

            saveDialog.Filter = "Excel文件|*.xls";

            saveDialog.FileName = fileName;

            MemoryStream ms = new MemoryStream();

            if (saveDialog.ShowDialog() == DialogResult.OK)

            {

                saveFileName = saveDialog.FileName;

                if (!CheckFiles(saveFileName))

                {

                    MessageBox.Show("文件被站用，请关闭文件 " + saveFileName);

                    workbook = null;

                    ms.Close();

                    ms.Dispose();

                    return;

                }

                FileStream file = new FileStream(saveFileName, FileMode.Create);

                workbook.Write(file);

                file.Close();

                MessageBox.Show(fileName + " 保存成功", "提示", MessageBoxButtons.OK);

            }

            else

            {

                workbook = null;

                ms.Close();

                ms.Dispose();

            }

        }



        /// <summary>

        /// 检测文件被占用 

        /// </summary>

        /// <param name="FileNames">要检测的文件路径</param>

        /// <returns></returns>

        public bool CheckFiles(string FileNames)

        {

            if (!File.Exists(FileNames))

            {

                //文件不存在

                return false;

            }

            else

            {

                IntPtr vHandle = _lopen(FileNames, OF_READWRITE | OF_SHARE_DENY_NONE);

                if (vHandle == HFILE_ERROR)

                {

                    return false;

                }

                CloseHandle(vHandle);

            }

            return true;

        }

　　3.定义jacket类

    public class Jacket

    {

        public string Type { get; set; }

        public string Color { get; set; }

        public string Size { get; set; }

        public decimal price { get; set; }

    }

　　4.判定文件是否打开

        [DllImport("kernel32.dll")]

        public static extern IntPtr _lopen(string lpPathName, int iReadWrite);



        [DllImport("kernel32.dll")]

        public static extern bool CloseHandle(IntPtr hObject);



        public const int OF_READWRITE = 2;

        public const int OF_SHARE_DENY_NONE = 0x40;

        public readonly IntPtr HFILE_ERROR = new IntPtr(-1);