c# 用OpenXmL读取.xlsx格式的Excel文件 返回DataTable

1.须要引用的dll :  DocumentFormat.OpenXml.dll  ---须要安装一下OpenXml再引用

                             WindowsBase  ---直接在项目里加入引用

2.方法：

/// <summary>
        /// 读取.xlsx格式的Excel文件数据，读取其特定名称的工作薄
        /// </summary>
        /// <param name="filePath">文件路径 如 D:\excel1.xls</param>
        /// <param name="sheetName">工作薄名称 如 Sheet1</param>
        /// <param name="fieldNames">要转化成的DataTable的列名数组</param>
        /// <returns></returns>
        public static DataTable ReadExcelToDataTable(Stream fileStream, string sheetName, string[] fieldNames)
        {

              using (var document = SpreadsheetDocument.Open(fileStream, false))
            {
                var sheets = document.WorkbookPart.Workbook.Descendants<Sheet>().Where(p => p.Name == sheetName);
                var enumerable = sheets as Sheet[] ??
 sheets.ToArray();
                if (!enumerable.Any())
                {
                    return null;
                }
                var wsp = (WorksheetPart)document.WorkbookPart.GetPartById(enumerable.First().Id);
                //获取Excel中共享数据
                var stringTable = document.WorkbookPart.SharedStringTablePart.SharedStringTable;
                var rows = wsp.Worksheet.Descendants<Row>();//获得Excel中得数据行
                DataTable table = new DataTable();
                foreach (var name in fieldNames)
                {
                    table.Columns.Add(name, typeof(string));
                }
                //由于需要将数据导入到DataTable中,所以我们假定Excel的第一行是列名,从第二行开端是行数据
                var _count = 0;
                var enumerable1 = rows as Row[] ?? rows.ToArray();
                var total = enumerable1.Count() - 1;
                foreach (var row in enumerable1)
                {
                    if (row.RowIndex > 1)
                    {
                        _count++;
                        GetDataRow(row, stringTable, ref table, fieldNames); //Excel第二行同一时候为DataTable的第一行数据
                        if (_count % 100 != 0) continue;
                        var per = (100 * _count / total - 5) <= 0 ? 1 : (100 * _count / total - 5);
                        var perS = per.ToString(CultureInfo.InvariantCulture) + "%";

                        HttpContext.Current.Response.Write("<script>top.process('" + perS + "');</script>");
                        HttpContext.Current.Response.Flush();
                    }
                }
                return table;
            }
        }
        /// 获取Excel行数据
        private static void GetDataRow(IEnumerable<OpenXmlElement> row, OpenXmlElement stringTable, ref DataTable table, string[] fieldNames)
        {
            if (stringTable == null) throw new ArgumentNullException("stringTable");
            var dic = new Dictionary<int, string>();
            var i = 0;
            foreach (Cell cell in row)
            {
                GetValue(i, cell, stringTable, ref dic);
                i++;
            }
            if (dic.Count == 0)
            {
                return;
            }
            var dr = table.NewRow();
            int index = 0;
            foreach (var name in fieldNames)
            {
                dr[name] = dic[index];
                index++;
            }
            table.Rows.Add(dr);
        }
        /// 获取Excel单元格数据       
        private static void GetValue(int i, CellType cell, OpenXmlElement stringTable, ref Dictionary<int, string> dic)
        {
            if (stringTable == null) throw new ArgumentNullException("stringTable");
            //由于Excel的数据存储在SharedStringTable中,需要获取数据在SharedStringTable 中的索引
            var value = string.Empty;
            try
            {
                if (cell.ChildElements.Count == 0)
                    return;
                value = cell.CellValue.InnerText;
                if ((cell.DataType != null) && (cell.DataType == CellValues.SharedString))
                {
                    value = stringTable.ChildElements[Int32.Parse(value)].InnerText;
                }
                dic.Add(i, value);

            }
            catch (Exception)
            {
            }
        }