使用 EPPlus，NPOI,操作EXCEL

NPOI,       读取xls文件(Excel2003及之前的版本)   (NPOI.dll+Ionic.Zip.dll)     http://npoi.codeplex.com/

EPPlus,    读取xlsx文件(Excel2007版本)                (EPPlus.dll)                       http://epplus.codeplex.com/

本文中只实现了Excel文件的读取,实际上,这两个控件均支持对其内容,格式,公式等进行修改,这些复杂功能尚无需求,所以没有实现

读取接口IExcel:

public interface IExcel
    {
        /// <summary> 打开文件 </summary>
        bool Open();
        /// <summary> 文件版本 </summary>
        ExcelVersion Version { get; }
        /// <summary> 文件路径 </summary>
        string FilePath { get; set; }
        /// <summary> 文件是否已经打开 </summary>
        bool IfOpen { get;  }
        /// <summary> 文件包含工作表的数量 </summary>
        int SheetCount { get; }
        /// <summary> 当前工作表序号 </summary>
        int CurrentSheetIndex { get; set; }
        /// <summary> 获取当前工作表中行数 </summary>
        int GetRowCount();
        /// <summary> 获取当前工作表中列数 </summary>
        int GetColumnCount();
        /// <summary> 获取当前工作表中某一行中单元格的数量 </summary>
        /// <param name="Row">行序号</param>
        int GetCellCountInRow(int Row);
        /// <summary> 获取当前工作表中某一单元格的值（按字符串返回） </summary>
        /// <param name="Row">行序号</param>
        /// <param name="Col">列序号</param>
        string GetCellValue(int Row, int Col);
        /// <summary> 关闭文件 </summary>
        void Close();
    }

public enum ExcelVersion
    {
        /// <summary> Excel2003之前版本 ,xls </summary>
        Excel03,
        /// <summary> Excel2007版本 ,xlsx  </summary>
        Excel07

xls文件实现:

using NPOI.HSSF.UserModel;

public class Excel03:IExcel
    {
        public Excel03()
        { }

        public Excel03(string path)
        { filePath = path; }

        private FileStream file = null;
        private string filePath = "";
        private HSSFWorkbook book = null;
        private int sheetCount=0;
        private bool ifOpen = false;
        private int currentSheetIndex = 0;
        private HSSFSheet currentSheet = null;
             
        public string FilePath
        {
            get  { return filePath; }
            set { filePath = value; }
        }

        public bool Open()
        {
            try
            {
                file = new FileStream(filePath, FileMode.Open, FileAccess.Read);
                book= new HSSFWorkbook(file);

                if (book == null) return false;
                sheetCount = book.NumberOfSheets;
                currentSheetIndex = 0;
                currentSheet = (HSSFSheet)book.GetSheetAt(0);
                ifOpen = true;
            }
            catch (Exception ex)
            {
                throw new Exception("打开文件失败，详细信息：" + ex.Message);
            }
            return true;
        }

        public void  Close()
        {
            if (!ifOpen) return;
            file.Close();
        }

        public ExcelVersion Version
        { get { return ExcelVersion.Excel03; } }

        public bool IfOpen
        { get { return ifOpen; } }

        public int SheetCount
        { get { return sheetCount; } }

        public int CurrentSheetIndex
        {
            get { return currentSheetIndex; }
            set 
            {
                if (value != currentSheetIndex)
                {
                    if (value >= sheetCount)
                        throw new Exception("工作表序号超出范围");
                    currentSheetIndex = value;
                    currentSheet = (HSSFSheet)book.GetSheetAt(currentSheetIndex);
                }
            }
        }

        public int GetRowCount()
        {
            if (currentSheet == null) return 0;
            return currentSheet.LastRowNum + 1;         
        }

        public int GetColumnCount()
        {
            if (currentSheet == null) return 0;
            int colCount = 0;
            for (int i = 0; i <= currentSheet.LastRowNum; i++)
            {
                if (currentSheet.GetRow(i) != null && currentSheet.GetRow(i).LastCellNum+1 > colCount)
                    colCount = currentSheet.GetRow(i).LastCellNum + 1;
            }
            return colCount;
        }

        public int GetCellCountInRow(int Row)
        {
            if (currentSheet == null) return 0;
            if (Row > currentSheet.LastRowNum) return 0;
            if (currentSheet.GetRow(Row) == null) return 0;

            return currentSheet.GetRow(Row).LastCellNum+1;
        }

        public string GetCellValue(int Row, int Col)
        {
            if (Row > currentSheet.LastRowNum) return "";
            if (currentSheet.GetRow(Row) == null) return "";
             HSSFRow r = (HSSFRow)currentSheet.GetRow(Row);

             if (Col > r.LastCellNum) return "";
             if (r.GetCell(Col) == null) return "";
             return r.GetCell(Col).StringCellValue;            
        }

xlsx文件实现:

using OfficeOpenXml;

public class Excel07:IExcel
    { 
        public Excel07()
        { }

        public Excel07(string path)
        { filePath = path; }

        private string filePath = "";
        private ExcelWorkbook book = null;
        private int sheetCount = 0;
        private bool ifOpen = false;
        private int currentSheetIndex = 0;
        private ExcelWorksheet currentSheet = null;
        private ExcelPackage ep = null;

        public bool Open()
        {
            try
            {
                ep = new ExcelPackage(new FileInfo(filePath));
                
                if (ep == null) return false;
                book =ep.Workbook;
                sheetCount = book.Worksheets.Count;
                currentSheetIndex = 0;
                currentSheet = book.Worksheets[1];
                ifOpen = true;
            }
            catch (Exception ex)
            {
                throw new Exception("打开文件失败，详细信息：" + ex.Message);
            }
            return true;
        }

        public void Close()
        {
            if (!ifOpen || ep == null) return;
            ep.Dispose();
        }

        public ExcelVersion Version
        { get { return ExcelVersion.Excel07; } }

        public string FilePath
        {
            get { return filePath; }
            set { filePath = value; }
        }

        public bool IfOpen
        { get { return ifOpen; } }

        public int SheetCount
        { get { return sheetCount; } }

        public int CurrentSheetIndex
        {
            get  { return currentSheetIndex; }
            set
            {
                if (value != currentSheetIndex)
                {
                    if (value >= sheetCount)
                        throw new Exception("工作表序号超出范围");
                    currentSheetIndex = value;
                    currentSheet =book.Worksheets[currentSheetIndex+1];
                }
            }
        }

        public int GetRowCount()
        {
            if (currentSheet == null) return 0;
            return currentSheet.Dimension.End.Row;
        }

        public int GetColumnCount()
        {
            if (currentSheet == null) return 0;
            return currentSheet.Dimension.End.Column;
        }

        public int GetCellCountInRow(int Row)
        {
            if (currentSheet == null) return 0;
            if (Row >= currentSheet.Dimension.End.Row) return 0;
            return currentSheet.Dimension.End.Column;
        }

        public string GetCellValue(int Row, int Col)
        {
            if (currentSheet == null) return "";
            if (Row >= currentSheet.Dimension.End.Row || Col >= currentSheet.Dimension.End.Column) return "";
            object tmpO =currentSheet.GetValue(Row + 1, Col + 1);
            if (tmpO == null) return "";
            return tmpO.ToString();
        }

调用类:

public class ExcelLib
    {
        /// <summary> 获取Excel对象 </summary>
        /// <param name="filePath">Excel文件路径</param>
        /// <returns></returns>
        public static IExcel GetExcel(string filePath)
        {
            if (filePath.Trim() == "") 
                throw new Exception("文件名不能为空");

            if(!filePath.Trim().EndsWith("xls") && !filePath.Trim().EndsWith("xlsx"))
                throw new Exception("不支持该文件类型");

            if (filePath.Trim().EndsWith("xls"))
            {
                IExcel res = new Excel03(filePath.Trim());
                return res;
            }
            else if (filePath.Trim().EndsWith("xlsx"))
            {
                IExcel res = new Excel07(filePath.Trim());
                return res;
            }
            else return null;
        }

调用：

ExcelLib.IExcel tmp = ExcelLib.ExcelLib.GetExcel(Application.StartupPath + "\TestUnicodeChars.xls");
//ExcelLib.IExcel tmp = ExcelLib.ExcelLib.GetExcel(Application.StartupPath + "\TestUnicodeChars.xlsx");
if (tmp == null) MessageBox.Show("打开文件错误");
try
{
if (!tmp.Open())
    MessageBox.Show("打开文件错误");
     tmp.CurrentSheetIndex = 1;
int asdf = tmp.GetColumnCount();
string sdf = tmp.GetCellValue(0,1);
    tmp.Close();
}
catch (Exception ex)
{ MessageBox.Show(ex.Message); return

                ExcelWorksheet ws = pck.Workbook.Worksheets.Add("Fix Asset");

                //Load the datatable into the sheet, starting from cell A1. Print the column names on row 1
                //ws.Cells["A1"].LoadFromDataTable(tbl, true);
                ws.Cells["A1"].LoadFromCollection(assets, true);//collection型数据源

                //写到客户端（下载）       
                Response.Clear();       
                Response.AddHeader("content-disposition", "attachment;  filename=FixAsset.xlsx");       
                Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
                Response.BinaryWrite(pck.GetAsByteArray());       
                //ep.SaveAs(Response.OutputStream);    第二种方式       
                Response.Flush();
                Response.End();  

注意：如果是在ASCX中调用，需要：

在Page_Load中注册两行Javascript脚本，string script = “_spOriginalFormAction = document.forms[0].action; _spSuppressFormOnSubmitWrapper = true;”; 

this.ClientScript.RegisterClientScriptBlock(this.GetType(), “script”, script, true); 

可以查看：http://www.cnblogs.com/ceci/archive/2012/09/05/2671538.html