当前文件路径：NChat/NChart.DBHelper/UserHelper.cs

		            
 1using System;
 2using System.Collections.Generic;
 3using System.Linq;
 4using System.Text;
 5using System.Data.Linq;
 6using System.Web;
 7using NChat.Common;
 8//该源码下载自www.51aspx.com(５１ａｓｐｘ．ｃｏｍ)
 9namespace NChart.DBHelper
10...{
11    public abstract class UserHelper
12    ...{
13        public static User Login(User user)
14        ...{
15            NChatDataContext context = NChatData.Instance;
16            var users = from u in context.Users
17                        where u.Name == user.Name && u.Password == user.Password
18                        select u;
19            if (users.Count() > 0)
20                return users.Single();
21            else
22            ...{
23                if (!IsExits(user))
24                ...{
25                    Register(user);
26                    return Login(user);
27                }
28                else
29                ...{
30                    user.ID = -1;
31                    return user;
32                }
33            }
34        }
35//5_1_a_s_p_x.c_o_m
36
37        public static bool IsExits(User user)
38        ...{
39            NChatDataContext context = NChatData.Instance;
40            var users = from u in context.Users
41                        where u.Name == user.Name
42                        select u;
43            if (users.Count() > 0)
44                return true;
45            else
46                return false;
47        }
48
49        public static void Register(User user)
50        ...{
51            NChatDataContext context = NChatData.Instance;
52            context.Users.InsertOnSubmit(user);
53            context.SubmitChanges();
54        }
55
56        public static IQueryable<User> Users()
57        ...{
58            NChatDataContext context = NChatData.Instance;
59            var users = from user in context.Users
60                                select user;
61            return users;
62        }
63    }
64}
65