C#的DataReader类使用例子

以下是C#的DataReader类实例代码：

using System;

using System.IO;

using System.Data;

using System.Data.OleDb;

namespace ConsoleDataReader

{

 /// <summary>

 /// Class1 的摘要说明。

 /// </summary>

 class DataReaderClass

 {

  /// <summary>

  /// 应用程序的主入口点。

  /// </summary>

  [STAThread]

  static void Main(string[] args)

  {

   string strCon = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=DataBase.mdb";

   OleDbConnection MyCon = new OleDbConnection(strCon);

   try

   {

    // 打开数据库的连接

    MyCon.Open();

    string strSQL = @"select * from ADODemo";

    OleDbCommand MyCom = new OleDbCommand(strSQL, MyCon);

    // 获取DataReader的数据集

    OleDbDataReader MyDataReader = MyCom.ExecuteReader();

    // 输出数据库字段的名称和类型

    Console.WriteLine("{0}:{1} {2}:{3}",

                                                                                                   MyDataReader.GetName(0).PadRight(6)

                                                                                                   , MyDataReader.GetDataTypeName(0).PadRight(5),

                  MyDataReader.GetName(2).PadRight(5),

                                                                                                    MyDataReader.GetDataTypeName(2).PadRight(5));

    // 获取ADODemo表中的字段总数

    Console.WriteLine("ADODemo表的字段总数:{0}\n"

                                                                                                                  , MyDataReader.FieldCount);

    // 另一种方法获取数据库数据

    while (MyDataReader.Read())

    {

     Console.WriteLine("{0} {1}", MyDataReader

                                                                                                                                       .GetString(0), MyDataReader.GetInt32(2));

    }

    // 返回一个DataTable，需要应用System.Data命名空间

    DataTable MyDataTable = MyDataReader.GetSchemaTable();

    foreach (DataRow row in MyDataTable.Rows)

    {

     foreach (DataColumn col in MyDataTable.Columns)

                                                                                                          Console.WriteLine(col.ColumnName + " = " + row[col]);

     Console.WriteLine("----------------------------------------");

    }

    MyDataReader.Close();

   }

   catch (Exception ex)

   {

    Console.WriteLine("{0}", ex.ToString());

   }

   finally

   {

    MyCon.Close();

   }

   Console.ReadLine();

  }

 }

}