用户登录验证

用户的登录随处可见，这个程序估计谁都会写，这里将会使用到数据库以及asp.net的一些比较基础的知识如内置对象，ashx.下面就来写下这个程序吧。

1.写一个数据库的连接类，在这个类的构造方法取得数据库连接

using System;
using System.Data;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
namespace login.bean
{
    public class DBConnection
    {
        SqlConnection conn = null;
        string path = AppDomain.CurrentDomain.BaseDirectory; 
        public DBConnection(){

            if (path.EndsWith(@"\bin\Debug") || path.EndsWith(@"\bin\Release"))
            {
                path = System.IO.Directory.GetParent(path).Parent.Parent.FullName;
                AppDomain.CurrentDomain.SetData("DataDirectory", path);
            }
           this.conn= new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDBFilename=|DataDirectory|\mydb.mdf;Integrated Security=True;User Instance=True");
        }

        public SqlConnection getConnection() {
            return this.conn;
        }
       
            
    }
}

2.登录页面

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="login.aspx.cs" Inherits="login._Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">

    <title>用户登录</title>
</head>
<body>
    <form id="form1" runat="server" action="ashx/ToLogin.ashx">
      用户名：<input type="text" name="name" id="name"/><br /><br />
      密码：<input type="password" name="password" id="password"/><br /><br />
      <input type="submit" value="登录"/>
      <input type="reset" value="取消"/>
    </form>
</body>
</html>

4。写一个ashx处理用户登录，登录成功就存session，跳转到成功页面反之的是登录页面

using System;
using System.Collections;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;
using System.Web.SessionState;
using System.Data.SqlClient;
using login.bean;
namespace login.ashx
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class ToLogin : IHttpHandler,IReadOnlySessionState
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/html";
           
            string name=context.Request["name"];
            string password = context.Request["password"];
            
            DBConnection conn = new DBConnection();
            conn.getConnection().Open();
            using (SqlCommand command = conn.getConnection().CreateCommand())
           {
              
                command.CommandText = "select count(id) from t_customer where name=@name and password=@password";
                command.Parameters.Add(new SqlParameter("name",name));
                command.Parameters.Add(new SqlParameter("password", password));
                int tem = Convert.ToInt32(command.ExecuteScalar());
                if (tem == 1)
                {
                  
                   
                     context.Session["username"]= name;
                     context.Session["password"] = password;
                    context.Server.Transfer("/success/success.aspx");
                   
                }
                else {
                    
                    context.Server.Transfer("/login.aspx");
                }
            
            }
           
            
           
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

这里的数据库操作可以防止sql注入，同时拼写sql语句我也是最恨的。

5.成功页面

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="success.aspx.cs" Inherits="login.success.success" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>登录成功</title>
</head>
<body>
   <% 
       string name =(string) Session["username"];
    %>
    你好，<%=name%>
</body>
</html>