C# NOPI 項目實戰(經典)(可下載項目源碼)

1 -.首先說明下項目目的:

    以前我有寫過一篇  "NPOI操做EXCEL" 

 

這篇文章主要介紹瞭如何安裝NPOI，以及NPOI具體如何使用，而且用具體實例介紹了excel導入到datagridview以及 datagridview如何導出到excel並保存。若是不清楚這塊的去我公衆號去搜索這篇文章閱讀。

      今天這篇文章主要是實現多個excel多張表格的合併，這個是咱們數據處理時候常常使用的一個功能，其實最佳的途徑是用excel自帶的power query（excel2016自帶，excel2016如下版本須要安裝插件），用這個功能你甚至不須要寫一句代碼，就能夠輕輕鬆鬆實現百萬計甚至千萬級數據操做，固然你也能夠用excel裏面的vba，這些均可以，可是這不是今天要將的內容，今天的內容就是要用C# 實現數據表格的合併。

2. 源碼:

npoi.cs

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

namespace npoi1
{
    public class NPOIExcel
    {
        /// <summary>
        /// 將excel導入到datatable
        /// </summary>
        /// <param name="filePath">excel路徑</param>
        /// <param name="isColumnName">第一行是不是列名</param>
        /// <returns>返回datatable</returns>
        public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
        {
            DataTable dataTable = null;
            FileStream fs = null;
            DataColumn column = null;
            DataRow dataRow = null;
            IWorkbook workbook = null;
            ISheet sheet = null;
            IRow row = null;
            ICell cell = null;
            int startRow = 0;
            try
            {
                using (fs = File.OpenRead(filePath))
                {
                    // 2007版本
                    if (filePath.IndexOf(".xlsx") > 0)
                        workbook = new XSSFWorkbook(fs);
                    // 2003版本
                    else if (filePath.IndexOf(".xls") > 0)
                        workbook = new HSSFWorkbook(fs);

                    if (workbook != null)
                    {
                        sheet = workbook.GetSheetAt(0);//讀取第一個sheet，固然也能夠循環讀取每一個sheet
                        dataTable = new DataTable();
                        if (sheet != null)
                        {
                            int rowCount = sheet.LastRowNum;//總行數
                            if (rowCount > 0)
                            {
                                IRow firstRow = sheet.GetRow(0);//第一行
                                int cellCount = firstRow.LastCellNum;//列數

                                //構建datatable的列
                                if (isColumnName)
                                {
                                    startRow = 1;//若是第一行是列名，則從第二行開始讀取
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        cell = firstRow.GetCell(i);
                                        if (cell != null)
                                        {
                                            if (cell.StringCellValue != null)
                                            {
                                                column = new DataColumn(cell.StringCellValue);
                                                dataTable.Columns.Add(column);
                                            }
                                        }
                                    }
                                }
                                else
                                {
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        column = new DataColumn("column" + (i + 1));
                                        dataTable.Columns.Add(column);
                                    }
                                }

                                //填充行
                                for (int i = startRow; i <= rowCount; ++i)
                                {
                                    row = sheet.GetRow(i);
                                    if (row == null) continue;

                                    dataRow = dataTable.NewRow();
                                    for (int j = row.FirstCellNum; j < cellCount; ++j)
                                    {
                                        cell = row.GetCell(j);
                                        if (cell == null)
                                        {
                                            dataRow[j] = "";
                                        }
                                        else
                                        {
                                            //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)
                                            switch (cell.CellType)
                                            {
                                                case CellType.Blank:
                                                    dataRow[j] = "";
                                                    break;
                                                case CellType.Numeric:
                                                    short format = cell.CellStyle.DataFormat;
                                                    //對時間格式（2015.12.五、2015/12/五、2015-12-5等）的處理
                                                    if (format == 14 || format == 31 || format == 57 || format == 58)
                                                        dataRow[j] = cell.DateCellValue;
                                                    else
                                                        dataRow[j] = cell.NumericCellValue;
                                                    break;
                                                case CellType.String:
                                                    dataRow[j] = cell.StringCellValue;
                                                    break;
                                            }
                                        }
                                    }
                                    dataTable.Rows.Add(dataRow);
                                }
                            }
                        }
                    }
                }
                return dataTable;
            }
            catch (Exception)
            {
                if (fs != null)
                {
                    fs.Close();
                }
                return null;
            }
        }

        /// <summary>
        /// 寫入excel
        /// </summary>
        /// <param name="dt">datatable</param>
        /// <param name="strFile">strFile</param>
        /// <returns></returns>
        public static bool DataTableToExcel(DataTable dt, string strFile)
        {
            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 XSSFWorkbook();//HSSFWorkbook:是操做Excel2003之前（包括2003）的版本，擴展名是.xls  XSSFWorkbook:是操做Excel2007的版本，擴展名是.xlsx
                    sheet = workbook.CreateSheet("Sheet0");//建立一個名稱爲Sheet0的表
                    int rowCount = dt.Rows.Count;//行數
                    int columnCount = dt.Columns.Count;//列數

                    //設置列頭
                    row = sheet.CreateRow(0);//excel第一行設爲列頭
                    for (int c = 0; c < columnCount; c++)
                    {
                        cell = row.CreateCell(c);
                        cell.SetCellValue(dt.Columns[c].ColumnName);
                    }

                    //設置每行每列的單元格,
                    for (int i = 0; i < rowCount; i++)
                    {
                        row = sheet.CreateRow(i + 1);
                        for (int j = 0; j < columnCount; j++)
                        {
                            cell = row.CreateCell(j);//excel第二行開始寫入數據
                            cell.SetCellValue(dt.Rows[i][j].ToString());
                        }
                    }
                    using (fs = File.OpenWrite(strFile))
                    {
                        workbook.Write(fs);//向打開的這個xls文件中寫入數據
                        result = true;
                    }
                }
                return result;
            }
            catch (Exception ex)
            {
                if (fs != null)
                {
                    fs.Close();
                }
                Console.WriteLine(ex.StackTrace + ex.Message);
                return false;
            }
        }

        /// <summary>
        /// Excel導入成Datable
        /// </summary>
        /// <param name="file">導入路徑(包含文件名與擴展名)</param>
        /// <returns></returns>
        public static DataTable ExcelToTable(string file ,int nSheet)
        {
            DataTable dt = new DataTable();
            IWorkbook workbook;
            string fileExt = Path.GetExtension(file).ToLower();
            using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
            {
                //XSSFWorkbook 適用XLSX格式，HSSFWorkbook 適用XLS格式
                if (fileExt == ".xlsx") { workbook = new XSSFWorkbook(fs); } else if (fileExt == ".xls") { workbook = new HSSFWorkbook(fs); } else { workbook = null; }
                if (workbook == null) { return null; }
                ISheet sheet = null;
                if (nSheet < workbook.NumberOfSheets) //爲了避免讓獲取超過表格數量最大索引致使報錯
                    sheet = workbook.GetSheetAt(nSheet);
                else
                { return null; }

                //表頭
                IRow header = sheet.GetRow(sheet.FirstRowNum);
                List<int> columns = new List<int>();
                for (int i = 0; i < header.LastCellNum; i++)
                {
                    object obj = GetValueType(header.GetCell(i));
                    if (obj == null || obj.ToString() == string.Empty)
                    {
                        dt.Columns.Add(new DataColumn("Columns" + i.ToString()));
                    }
                    else
                        dt.Columns.Add(new DataColumn(obj.ToString()));
                    columns.Add(i);
                }
                //數據
                for (int i = sheet.FirstRowNum + 1; i <= sheet.LastRowNum; i++)
                {
                    DataRow dr = dt.NewRow();
                    bool hasValue = false;
                    foreach (int j in columns)
                    {
                        dr[j] = GetValueType(sheet.GetRow(i).GetCell(j));
                        if (dr[j] != null && dr[j].ToString() != string.Empty)
                        {
                            hasValue = true;
                        }
                    }
                    if (hasValue)
                    {
                        dt.Rows.Add(dr);
                    }
                }
            }
            return dt;
        }

        /// <summary>
        /// Datable導出成Excel
        /// </summary>
        /// <param name="dt"></param>
        /// <param name="file">導出路徑(包括文件名與擴展名)</param>
        public static void TableToExcel(DataTable[] dt, string file , int nSheet)
        {
            IWorkbook workbook;
            string fileExt = Path.GetExtension(file).ToLower();
            if (fileExt == ".xlsx") { workbook = new XSSFWorkbook(); } else if (fileExt == ".xls") { workbook = new HSSFWorkbook(); } else { workbook = null; }
            if (workbook == null) { return; }
            ISheet[] sheet = new ISheet[nSheet];
            for (int k = 0; k < nSheet; k++)
            {
                if (dt[k] != null)
                {
                    sheet[k] = string.IsNullOrEmpty(dt[k].TableName) ? workbook.CreateSheet("Sheet" + (k + 1).ToString()) : workbook.CreateSheet(dt[k].TableName);

                    //表頭
                    IRow row = sheet[k].CreateRow(0);
                    for (int i = 0; i < dt[k].Columns.Count; i++)
                    {
                        ICell cell = row.CreateCell(i);
                        cell.SetCellValue(dt[k].Columns[i].ColumnName);
                    }

                    //數據
                    for (int i = 0; i < dt[k].Rows.Count; i++)
                    {
                        IRow row1 = sheet[k].CreateRow(i + 1);
                        for (int j = 0; j < dt[k].Columns.Count; j++)
                        {
                            ICell cell = row1.CreateCell(j);
                            cell.SetCellValue(dt[k].Rows[i][j].ToString());
                        }
                    }
                }
                else
                   continue;
            }
           

   

            //轉爲字節數組
            MemoryStream stream = new MemoryStream();
            workbook.Write(stream);
            var buf = stream.ToArray();

            //保存爲Excel文件
            using (FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write))
            {
                fs.Write(buf, 0, buf.Length);
                fs.Flush();
            }
        }

        /// <summary>
        /// 獲取單元格類型
        /// </summary>
        /// <param name="cell"></param>
        /// <returns></returns>
        private static object GetValueType(ICell cell)
        {
            if (cell == null)
                return null;
            switch (cell.CellType)
            {
                case CellType.Blank: //BLANK:
                    return null;
                case CellType.Boolean: //BOOLEAN:
                    return cell.BooleanCellValue;
                case CellType.Numeric: //NUMERIC:
                    return cell.NumericCellValue;
                case CellType.String: //STRING:
                    return cell.StringCellValue;
                case CellType.Error: //ERROR:
                    return cell.ErrorCellValue;
                case CellType.Formula: //FORMULA:
                default:
                    return "=" + cell.CellFormula;

            }
        }

    }


}

　　mainForm.cs

using NPOI.SS.UserModel;
using System;
using System.Data;
using System.Diagnostics;
using System.IO;
using System.Windows.Forms;

namespace npoi1
{
    public partial class mainForm : Form
    {
        public mainForm()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }
        public static int sheetCount=5;//定義表的最大數量
        DataTable[] lastTable = new DataTable[sheetCount];

        private void button1_Click(object sender, EventArgs e)
        {
            Stopwatch sw = new Stopwatch();
            sw.Start();
            //dataGridView1.DataSource = NPOIExcel.ExcelToDataTable("電腦統計表.xlsx", true);//方式1
            DataTable[] tempTable = new DataTable[sheetCount];
            DirectoryInfo dir = new DirectoryInfo(@"C:\Users\TPS20\Desktop\excel\");
            for (int i = 0; i < sheetCount; i++) //遍歷一個excel的每一個sheet
            {
                bool flag = true;
                foreach (FileInfo dChild in dir.GetFiles("*.xlsx"))//遍歷文件夾下的xlsx文件
                {
                    tempTable[i] =  NPOIExcel.ExcelToTable(dChild.FullName, i);//方式2

                    if (flag && lastTable[i] == null&& tempTable[i] != null) //第一次直接賦值，使得lastTable[i]獲取表結構不爲null
                    {

                        lastTable[i] = tempTable[i];

                        flag = false;
                    }
                    if (tempTable[i]!=null)
                    GetAllDataTable(tempTable[i] , i);//DataTable合併
                }              
            }

            NPOIExcel.TableToExcel(lastTable, @"C:\Users\TPS20\Desktop\excel\1\111.xlsx", sheetCount);//方式2
            dataGridView1.DataSource = lastTable[0];//調試時候顯示用的，能夠去掉
            dataGridView2.DataSource = lastTable[1];//調試時候顯示用的，能夠去掉
            dataGridView3.DataSource = lastTable[2];//調試時候顯示用的，能夠去掉
            sw.Stop();
            label1.Text = sw.ElapsedMilliseconds.ToString("數據導入耗時：" + "0000"+"ms");
            MessageBox.Show("數據導入完成");
        }

        public void GetAllDataTable(DataTable dt,int nSheet)
        {
            if(lastTable[nSheet]!=null)
            lastTable[nSheet].Merge(dt, false, MissingSchemaAction.AddWithKey);


        }

        private void dataGridView1_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e)
        {
            for (int i = 0; i < dataGridView1.Rows.Count; i++)

                this.dataGridView1.Rows[i].HeaderCell.Value = (i + 1).ToString();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //Stopwatch sw = new Stopwatch();
            //sw.Start();
            //DataTable dt = (dataGridView1.DataSource as DataTable);
            ////NPOIExcel.DataTableToExcel(dt, "d:\\111.xlsx");//方式1
            //NPOIExcel.TableToExcel(dt, "d:\\111.xlsx",0);//方式2
            //sw.Stop();
            //label2.Text = sw.ElapsedMilliseconds.ToString("數據導出耗時：" + "0000" + "ms");
            //MessageBox.Show("數據導出完成");
        }
    }

}

　　3. 運行效果

 

 

4.源碼百度網盤下載地址：

 

連接：https://pan.baidu.com/s/1L0rv_CM0N4FTZ-fpwS-YXA 

提取碼：cjj8 

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