CS0143: 类型“System.Data.OracleClient.OracleDataReader”未定义构造函数
运行程序时，出现了题目中的错误
错误行在 ：OracleDataReader odr = new OracleDataReader();
请大家帮忙解决啊！！！

using System;
using System.Collections;
using System.ComponentModel;
using System.Configuration;
using System.Data;
using System.Data.OracleClient;
using System.Drawing;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text;

public partial class _Default : System.Web.UI.Page
{
protected void ButtonLogin_Click(object sender, EventArgs e)
{
string sUserID, sPassword, sUserName, sUserLvl, sCompany;

//增加了对于验证码得判断 2007－3－1 congcong
string sConfirmCode,sSessionConfirmCode;
sConfirmCode = TextBoxConfirmCode.Text;
sSessionConfirmCode = Session["ConfirmCode"].ToString();
if (sConfirmCode != sSessionConfirmCode)
{
Response.Redirect("错误报告.aspx?ErrorCode=验证码输入错误！请返回，重新输入");
}

// 增加代码结束 2007－3－1 congcong

sUserID = TextBoxUserID.Text;
sPassword = TextBoxUserPassword.Text;

LabelWelcome.Text = sUserID;
string sConnectionString, sSelectCommand;

sConnectionString = ConfigurationManager.ConnectionStrings["OraConnectionString"].ConnectionString;
OracleConnection MyConnection = new System.Data.OracleClient.OracleConnection(sConnectionString);

sSelectCommand = "scott.P_CHECK_USER_PASSWORD";
OracleCommand MyCommand = new OracleCommand();
MyCommand.Connection = MyConnection;
MyCommand.CommandText = sSelectCommand;
MyCommand.CommandType = CommandType.StoredProcedure;

MyCommand.Parameters.Add("vUserID", OracleType.VarChar).Value = sUserID;
MyCommand.Parameters.Add("vUserPassword", OracleType.VarChar).Value = sPassword;
MyCommand.Parameters.Add("vUserlvl", OracleType.VarChar, 1).Direction = ParameterDirection.Output;
MyCommand.Parameters.Add("CountUser", OracleType.Number).Direction = ParameterDirection.Output;
MyCommand.Parameters.Add("vUserName", OracleType.VarChar, 20).Direction = ParameterDirection.Output;
MyCommand.Parameters.Add("vCompany", OracleType.VarChar, 20).Direction = ParameterDirection.Output;

MyCommand.Connection.Open();
MyCommand.ExecuteNonQuery();

if (Convert.ToInt32(MyCommand.Parameters["CountUser"].Value) == 0)
{
Response.Redirect("错误报告.aspx?ErrorCode=5");
return;
}
else if (MyCommand.Parameters["CountUser"].Value == null)
{
Response.Redirect("错误报告.aspx?ErrorCode=6");
return;
}
else if (Convert.ToInt32(MyCommand.Parameters["CountUser"].Value) != 1)
{
Response.Redirect("错误报告.aspx?ErrorCode=不可预知的错误");
return;
}

sUserName = MyCommand.Parameters["vUserName"].Value.ToString();
sCompany = MyCommand.Parameters["vCompany"].Value.ToString();
sUserLvl = MyCommand.Parameters["vUserlvl"].Value.ToString();
LabelWelcome.Text = "欢迎你光临XXXXXXXX：" + sUserName;

Session["UserID"] = sUserID;
Session["UserName"] = sUserName;
Session["UserLvl"] = sUserLvl;
Session["Company"] = sCompany;

string sSelectCommand1;//qrj edit at 2007.10.08
//增加对于用户冻结状态的判断

sSelectCommand1 = "select userstatu from scott.netusersearch where userid = :userid";
OracleCommand MyCommand1 = new OracleCommand();
MyCommand1.Connection = MyConnection;
MyCommand1.CommandText = sSelectCommand1;
MyCommand1.CommandType = CommandType.Text;
MyCommand1.Parameters.Add(":userid", OracleType.VarChar).Value = sUserID;

MyCommand1.Connection.Open();

OracleDataReader odr = new OracleDataReader();

odr = MyCommand1.ExecuteReader();

string sStatu;
if (odr.Read())
{
sStatu = odr[0].ToString();
}
else
{
Response.Redirect("错误报告.aspx?ErrorCode=不存在输入的用户ID");
return;
}
odr.Close();

if (sStatu == "0")
{
Response.Redirect("错误报告.aspx?ErrorCode=输入的用户ID的用户已经处于冻结状态，需要解除冻结才能登录！");
return;
}

MyCommand.Connection.Close();

Response.Redirect("load.aspx");
}
}




[解决办法]
直接定义，不用构造
OracleDataReader odr
odr = MyCommand1.ExecuteReader();


[解决办法]
ＬＳ的说的对

MyCommand1.Connection.Open();

OracleDataReader odr = new OracleDataReader();

odr = MyCommand1.ExecuteReader();

string sStatu;
if (odr.Read())
－－－－－＞
MyCommand1.Connection.Open();

OracleDataReader odr ＝MyCommand1.ExecuteReader();

string sStatu;
if (odr.Read())
[解决办法]
OracleDataReader没有公共的构造函数，
是通过 OracleCommand类实例的
public System.Data.OracleClient.OracleDataReader ExecuteReader()
方法创建的
[解决办法]
不能用new例化一象，因他有公共的造函。