总是编译不过去，连接被关闭

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OracleClient;
using System.Configuration;

namespace 登录
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)
        {
            OracleConnection Neu = new OracleConnection("Data Source=orcl;User ID=neu;Password=oracle;Unicode=True");

            Neu.Open();

            OracleCommand cmd = new OracleCommand();

            cmd.CommandText = string.Format("Select uname,password from user_log where uname=" + textBox1.Text);

            OracleDataReader sdr = cmd.ExecuteReader();
            while (sdr.Read())
            {


                if (textBox1.Text.Equals(sdr[1]) && textBox2.Text.Equals(sdr[2]))
                {
                    Form2 f = new Form2();
                    label3.Text = "登录成功";
                    f.ShowDialog();
                }
                else
                {
                    label3.Text = "登录失败";
                }
            }
        }


        private void label3_Click(object sender, EventArgs e)
        {

        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.PasswordChar = '*';
            textBox2.PasswordChar = '*';
        }


    }
}
--------------------编程问答-------------------- --------------------编程问答-------------------- cmd没有指定connection --------------------编程问答-------------------- 这不叫“编译不过去”吧 --------------------编程问答-------------------- cmd.Connection=Neu;
加到你那句前面.

补充：.NET技术 ,  其他语言