conn.cs

用三层架构写的用户登录的简单例子 适合C#初学者

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;


namespace DAl
{
    public class Conn
    {
        string str_Conn = "Data Source=zhangchen;Initial Catalog=xuesheng;Integrated Security=True";
        SqlConnection sqlConn;

        public void DbConn()
        {
            sqlConn = new SqlConnection(str_Conn);
            sqlConn.Open();
        }

        public DataTable Getdata(string sqlstr)
        {
            SqlDataAdapter sqlda = new SqlDataAdapter(sqlstr,sqlConn);
            DataTable dt = new DataTable();
            sqlda.Fill(dt);
            return dt;
        }

        public void Dosql(string sqlstr)
        {
            SqlCommand sqlCom = new SqlCommand(sqlstr, sqlConn);
            sqlCom.ExecuteNonQuery();
        }
        public void CloseDB()
        {
            if (sqlConn.State == ConnectionState.Open)
            {
                sqlConn.Close();
            }
        }
    }
}