#应用openxml读写excel代码

这个例子比较简单，没有考虑格式之类的问题。

using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
namespace JobTool
{
    public class ExcelBll
    {
        private void GetColumnNameAndRowIndex(string cellReference, out string columnName, out UInt32 rowIndex)
        {
            var regex = new Regex("[A-Za-z]+");
            var match = regex.Match(cellReference);
            columnName = match.Value;
            string s = cellReference.Replace(columnName, "");
            rowIndex = UInt32.Parse(s);
        }
        public List<ExcelCellEntity> ReadExcel(string excelPath, int columnCount, int rowCount)
        {
            List<ExcelCellEntity> ret = new List<ExcelCellEntity>();
            using (SpreadsheetDocument document = SpreadsheetDocument.Open(excelPath, false))
            {
                WorkbookPart wbPart = document.WorkbookPart;
                var sheet = wbPart.Workbook.Descendants<Sheet>().FirstOrDefault();
                WorksheetPart worksheet = (WorksheetPart)wbPart.GetPartById(sheet.Id);
                SheetData SheetData1 = worksheet.Worksheet.Elements<SheetData>().FirstOrDefault();
                foreach (var inst in SheetData1.Descendants<Cell>())
                {
                    ExcelCellEntity entity = new ExcelCellEntity();
                    ret.Add(entity);
                    entity.Value = this.GetValue(inst, wbPart);
                    string columnName = "";
                    UInt32 rowIndex = 1;
                    GetColumnNameAndRowIndex(inst.CellReference, out columnName, out rowIndex);
                    entity.Column = columnName;
                    entity.Row = rowIndex;
                }
            }
            return ret;
        }
        public void WriteExcel(string excelPath, List<ExcelCellEntity> datas)
        {
            File.Copy("blank.xlsx", excelPath, true);
            List<ExcelCellEntity> ret = new List<ExcelCellEntity>();
            using (SpreadsheetDocument document = SpreadsheetDocument.Open(excelPath, true))
            {
                WorkbookPart wbPart = document.WorkbookPart;
                var sheet = wbPart.Workbook.Descendants<Sheet>().FirstOrDefault();
                WorksheetPart worksheet = (WorksheetPart)wbPart.GetPartById(sheet.Id);
                SheetData SheetData1 = worksheet.Worksheet.Elements<SheetData>().FirstOrDefault();
                foreach (var inst in datas)
                {
                    this.WriteExcel1(SheetData1, inst.Column, inst.Row, inst.Value);
                }
                wbPart.Workbook.Save();
            }
        }
        private Cell CreateTextCell(string header, UInt32 index, string text)
        {
            var cell = new Cell
            {
                DataType = CellValues.InlineString,
                CellReference = header + index
            };
            var istring = new InlineString();
            var t = new Text { Text = text };
            istring.AppendChild(t);
            cell.AppendChild(istring);
            return cell;
        }
        private void WriteExcel1(SheetData sheetData, string header, UInt32 index, string text)
        {
            Row r1 = sheetData.Descendants<Row>().Where(a => a.RowIndex == index).FirstOrDefault();
            if (r1 == null)
            {
                r1 = new Row() { RowIndex = index };
                sheetData.Append(r1);
            }
            r1.Append(CreateTextCell(header, index, text));
        }
        public String GetValue(Cell cell, WorkbookPart wbPart)
        {
            SharedStringTablePart stringTablePart = wbPart.SharedStringTablePart;
            if (cell.ChildElements.Count == 0)
                return null;
            String value = cell.CellValue.InnerText;
            if ((cell.DataType != null) && (cell.DataType == CellValues.SharedString))
                return stringTablePart.SharedStringTable.ChildElements[Int32.Parse(value)].InnerText;
            return value;
        }
    }
}