Excel 文件 - 它已被其他用户以独占方式打开，

我正在使用 C# 读取 excel 文件，下面是按预期工作的代码，除了每次运行应用程序时，我都必须关闭 excel 文件，否则我会收到以下错误消息：

The Microsoft Access database engine cannot open or write to the file ''. It is already opened exclusively by another user, or you need permission to view and write its data..

我的问题是：有没有办法在我读完之后关闭Excel文件？

public static  DataTable LoadExcelWorkbook(string workbookName)
        {
            OleDbConnection connection;

            string connectionString = String.Format(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=""Excel 8.0;HDR=YES;IMEX=1;""", EXCELFILENAME);
            string query = String.Format("select * from [{0}$]", workbookName);

            using(OleDbConnection conn = new OleDbConnection(connectionString))
            {
                connection = new OleDbConnection(connectionString);
                connection.Open();

                OleDbDataAdapter dataAdapter = new OleDbDataAdapter(query, connectionString);
                DataSet dataSet = new DataSet();
                dataAdapter.Fill(dataSet);

                DataTable myTable = dataSet.Tables[0];

                dataAdapter.Dispose();
                connection.Close();
                dataSet.Dispose();            

                //CLOSE THE EXCEL FILE?????????

                if (myTable != null)
                    return myTable;

                return null; 
            } 
        }

使用工作表名称代替工作簿名称