C#读取excel--OLEDB方式

这里贴的代码是读取本地文件系统中的excel

 //读取EXCEL的方法   (用范围区域读取数据)    
        private  static DataTable GetExcelTableByOleDB(string excelFilePath)
        {
            //Excel连接
            OleDbConnection conn = null;
            DataTable dataTable = null;
            try
            {               
                //数据表
                DataSet ds = new DataSet();
                //获取文件扩展名
                string extension = System.IO.Path.GetExtension(excelFilePath);
                string fileName = System.IO.Path.GetfileName(excelFilePath);
                switch (extension)
                {
                    //HDR=YES,略过第一行数据;IMEX=1,只读方式打开
                    case ".xls":
                        conn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + excelFilePath + ";" + "Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1;\"");
                        break;
                    case ".xlsx":
                        conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelFilePath + ";" + "Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1;\"");
                        break;
                    default:
                        conn = null;
                        break;
                }
                if (conn == null)
                {
                    return null;
                }
                conn.Open();
                //获取Excel中所有Sheet表的信息
                System.Data.DataTable schemaTable = conn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null);
                //获取Excel的第一个Sheet表名
                string tableName = schemaTable.Rows[0][2].ToString().Trim();
                string strSql = "select * from [" + tableName + "]";
                //获取Excel指定Sheet表中的信息
                OleDbCommand objCmd = new OleDbCommand(strSql, conn);
                OleDbDataAdapter myData = new OleDbDataAdapter(strSql, conn);
                myData.Fill(ds, tableName);//填充数据              
                //dataTable即为excel文件中指定表中存储的信息
                dataTable = ds.Tables[tableName];               
            }
            catch(Exception e){
                ExceptionHelper.throwException(e, "解析excel文件出错");
            }          
            finally
            {
                if (conn != null) { conn.Close(); }
            }
            return dataTable;
        }