c#读取excel文件内容

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.OleDb;
using System.IO;

namespace DataCollect
{
    /// <summary>
    /// 读取excel信息的类
    /// </summary>
    internal class ExcelUtils
    {

        /// <summary>
        /// 读取excel及csv表格的内容
        /// </summary>
        /// <param name="pathName">文件路径</param>
        /// <param name="sheetName">sheet的name，如果只有一个或不指定，则传空</param>
        /// <returns></returns>
        /// <exception cref="Exception"></exception>
        public static DataTable ExcelToDataTable(string pathName, string sheetName)
        {
            int symbol = 0;
            DataTable tbContainer = new DataTable();
            string strConn = string.Empty; //创建一个空的 string（字段）对象 strConn；
            if (string.IsNullOrEmpty(sheetName)) { sheetName = "Sheet1"; }
            FileInfo file = new FileInfo(pathName);
            if (!file.Exists) {
                LogUtils.Error("文件不存在");
                throw new Exception("文件不存在"); }
            string extension = file.Extension;
            switch (extension)
            {
                case ".xls":
                    strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'";
                    break;
                case ".xlsx":
                    strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + pathName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'";
                    break;
                case ".CSV":
                    strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + sheetName + ";Extended Properties='Text;FMT=Delimited;HDR=YES'";
                    symbol = 1;
                    break;
                default:
                    strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'";
                    break;
            }
            //链接Excel
            OleDbConnection cnnxls = new OleDbConnection(strConn);

            if (symbol == 0)
            {
                OleDbDataAdapter oda = new OleDbDataAdapter(string.Format("select * from [{0}$]", sheetName), cnnxls);
                //将Excel里面有表内容装载到内存表中！
                oda.Fill(tbContainer);
            }
            else
            {
                OleDbDataAdapter myCommand = new OleDbDataAdapter("select * from " + pathName, strConn);
                myCommand.Fill(tbContainer);
            }
            // 判断行的数据是否为null，如果是，则进行删除该行
            List<DataRow> removeRowList = new List<DataRow>();
            foreach (DataRow r  in tbContainer.Rows) {
                if (r.ItemArray[0] == null || string.IsNullOrWhiteSpace(r.ItemArray[0].ToString())) {
                    removeRowList.Add(r);
                }
            }
            if (removeRowList.Count > 0) {
                foreach (DataRow r in removeRowList) {
                    tbContainer.Rows.Remove(r);
                }
            }
            return tbContainer;
        }
    }
}