linq to sql记录

//最近学习了一下Linq To Sql 在这里记录一下,备用
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;
namespace WindowsFormsApplication3
{
    using LinqSpace;
    using System.Data.Linq;
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            try
            {
                //System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection("server=DATABASE-VPC\\SQL2000;uid=Jiang;pwd=admin;database=Jiang");
                //conn.Open();
                UserDataContext db = new UserDataContext("server=DATABASE-VPC\\SQL2000;uid=Jiang;pwd=admin;database=Jiang");
                var users = from u in db.Users select u;//db.UsersInfo where u.UserName == s.UserName select u;
                foreach (var a in users)
                    this.listBox1.Items.Add(a.Uid);
            }
            catch (Exception ex) { MessageBox.Show(ex.Message); }
        }
        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            UserDataContext db = new UserDataContext("server=DATABASE-VPC\\SQL2000;uid=Jiang;pwd=admin;database=Jiang");
            System.IO.StreamWriter sw = new System.IO.StreamWriter(Application.StartupPath + (@"/abc.txt"), true);
            db.Log = sw;
            int aaa = (int)this.listBox1.SelectedItem;
            //var s = from u in db.Users from p in u.UsersInfo where u.Uid == aaa select p;
            var users = from u in db.Users from i in u.UsersInfo where u.Uid == aaa select i;
            this.listBox2.Items.Clear();
            foreach (var a in users)
                this.listBox2.Items.Add(a.UserName);
            sw.Close();
        }
        private void button1_Click(object sender, EventArgs e)
        {
            UserDataContext db = new UserDataContext("server=DATABASE-VPC\\SQL2000;uid=Jiang;pwd=admin;database=Jiang");
            this.listBox1.Items.Clear();
            var Eidt = db.Users.Single(x => x.Uid == 2);
            Eidt.UserName = "蒋金颖123";
            db.SubmitChanges();
            var users = from s in db.Users select s;
            foreach (var a in users)
                this.listBox2.Items.Add(a.UserName.ToString() + " " + a.Uid.ToString());
        }
    }
    public class UserDataContext : DataContext
    {
        public Table<Users> Users;
        //public Table<UsersInfo> UsersInfo;
        public UserDataContext(IDbConnection conn) : base(conn) { }
        public UserDataContext(string conn) : base(conn) { }
    }
}
namespace LinqSpace
{
    using System.Data.Linq.Mapping;
    using System.Data.Linq;
    [Table(Name = "cdb_members")]
    public class Users
    {
        [Column(IsPrimaryKey = true)]
        public int Uid;
        [Column]
        public string UserName;
        [Column]
        public string PASSWORD;
        private EntitySet<UsersInfo> usersinfo;
        [Association(Storage = "usersinfo", OtherKey = "Uid")]
        public EntitySet<UsersInfo> UsersInfo
        {
            get { return this.usersinfo; }
            set { this.usersinfo.Assign(value); }
        }
    }
    [Table(Name = "cdb_membersinfo")]
    public class UsersInfo
    {
        
        [Column(IsPrimaryKey=true)]
        public int Fid;
        [Column]
        public int Uid;
        [Column]
        public string UserName;
        [Column]
        public string Sex;
        [Column]
        public int Age;
        [Column]
        public string ADDRESS;
        [Column]
        public string Tel;
        [Column]
        public string Phone;
        private EntityRef<Users> users;
        [Association(Storage = "users", ThisKey = "Uid")]
        public Users Users
        {
            get { return this.users.Entity; }
            set { this.users.Entity = value; }
        }
        
    }
}
原文地址:https://www.cnblogs.com/server126/p/2057386.html