1 -.首先说明下项目目的:
之前我有写过一篇 "NPOI操作EXCEL"
这篇文章主要介绍了如何安装NPOI,以及NPOI具体如何使用,并且用具体实例介绍了excel导入到datagridview以及 datagridview如何导出到excel并保存。如果不清楚这块的去我公众号去搜索这篇文章阅读。
今天这篇文章主要是实现多个excel多张表格的合并,这个是我们数据处理时候经常使用的一个功能,其实最佳的途径是用excel自带的power query(excel2016自带,excel2016以下版本需要安装插件),用这个功能你甚至不需要写一句代码,就可以轻轻松松实现百万计甚至千万级数据操作,当然你也可以用excel里面的vba,这些都可以,但是这不是今天要将的内容,今天的内容就是要用C# 实现数据表格的合并。
2. 源码:
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> /// 将excel导入到datatable /// </summary> /// <param name="filePath">excel路径</param> /// <param name="isColumnName">第一行是否是列名</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);//读取第一个sheet,当然也可以循环读取每个sheet dataTable = new DataTable(); if (sheet != null) { int rowCount = sheet.LastRowNum;//总行数 if (rowCount > 0) { IRow firstRow = sheet.GetRow(0);//第一行 int cellCount = firstRow.LastCellNum;//列数 //构建datatable的列 if (isColumnName) { startRow = 1;//如果第一行是列名,则从第二行开始读取 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; //对时间格式(2015.12.5、2015/12/5、2015-12-5等)的处理 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> /// 写入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:是操作Excel2003以前(包括2003)的版本,扩展名是.xls XSSFWorkbook:是操作Excel2007的版本,扩展名是.xlsx 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 //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()); } } using (fs = File.OpenWrite(strFile)) { workbook.Write(fs);//向打开的这个xls文件中写入数据 result = true; } } return result; } catch (Exception ex) { if (fs != null) { fs.Close(); } Console.WriteLine(ex.StackTrace + ex.Message); return false; } } /// <summary> /// Excel导入成Datable /// </summary> /// <param name="file">导入路径(包含文件名与扩展名)</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 适用XLSX格式,HSSFWorkbook 适用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) //为了不让获取超过表格数量最大索引导致报错 sheet = workbook.GetSheetAt(nSheet); else { return null; } //表头 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); } //数据 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导出成Excel /// </summary> /// <param name="dt"></param> /// <param name="file">导出路径(包括文件名与扩展名)</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); //表头 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); } //数据 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; } //转为字节数组 MemoryStream stream = new MemoryStream(); workbook.Write(stream); var buf = stream.ToArray(); //保存为Excel文件 using (FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write)) { fs.Write(buf, 0, buf.Length); fs.Flush(); } } /// <summary> /// 获取单元格类型 /// </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;//定义表的最大数量 DataTable[] lastTable = new DataTable[sheetCount]; private void button1_Click(object sender, EventArgs e) { Stopwatch sw = new Stopwatch(); sw.Start(); //dataGridView1.DataSource = NPOIExcel.ExcelToDataTable("电脑统计表.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++) //遍历一个excel的每个sheet { bool flag = true; foreach (FileInfo dChild in dir.GetFiles("*.xlsx"))//遍历文件夹下的xlsx文件 { tempTable[i] = NPOIExcel.ExcelToTable(dChild.FullName, i);//方式2 if (flag && lastTable[i] == null&& tempTable[i] != null) //第一次直接赋值,使得lastTable[i]获取表结构不为null { lastTable[i] = tempTable[i]; flag = false; } if (tempTable[i]!=null) GetAllDataTable(tempTable[i] , i);//DataTable合并 } } NPOIExcel.TableToExcel(lastTable, @"C:\Users\TPS20\Desktop\excel\1\111.xlsx", sheetCount);//方式2 dataGridView1.DataSource = lastTable[0];//调试时候显示用的,可以去掉 dataGridView2.DataSource = lastTable[1];//调试时候显示用的,可以去掉 dataGridView3.DataSource = lastTable[2];//调试时候显示用的,可以去掉 sw.Stop(); label1.Text = sw.ElapsedMilliseconds.ToString("数据导入耗时:" + "0000"+"ms"); MessageBox.Show("数据导入完成"); } 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("数据导出耗时:" + "0000" + "ms"); //MessageBox.Show("数据导出完成"); } } }
3. 运行效果
4.源码百度网盘下载地址:
链接:https://pan.baidu.com/s/1L0rv_CM0N4FTZ-fpwS-YXA
提取码:cjj8
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