带验证码登录

随机生成验证码ValidateCode.ashx

 

<%@ WebHandler Language="C#" Class="ValidateCode" %>



using System;

using System.Web;

using System.Drawing;

using System.Web.SessionState;

//一般处理程序中使用session,必须实现一个接口

public class ValidateCode : IHttpHandler,IRequiresSessionState {



    public void ProcessRequest(HttpContext context)

    {

        context.Response.ContentType = "image/jpeg";

        string code = GetRndStr();  //生成4个随机的字符

        

        //记录生成的验证码

        context.Session["code"] = code;

        

        using (Bitmap img = CreateImages(code, "ch"))

        {

            img.Save(context.Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);

        }

    }



    public bool IsReusable

    {

        get

        {

            return false;

        }

    }

    /// <summary>

    /// 数字随机数

    /// </summary>

    /// <returns></returns>

    private string GetRndNum()

    {

        string code = string.Empty;

        Random random = new Random();

        for (int i = 0; i < 4; i++)

        {

            code += random.Next(9);

        }

        return code;

    }

    /// <summary>

    ///  英文随机

    /// </summary>

    /// <returns></returns>

    private string GetRndStr()

    {

        string Vchar = "A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";

        string[] VcArray = Vchar.Split(',');

        string checkCode = string.Empty;

        Random rand = new Random();

        for (int i = 0; i < 4; i++)

        {

            int t = rand.Next(VcArray.Length);

            checkCode += VcArray[t];

        }

        return checkCode;

    }

    /// <summary>

    /// 中文随机

    /// </summary>

    /// <returns></returns>

    private string GetRndCh()

    {

        System.Text.Encoding gb = System.Text.Encoding.Default;//获取GB2312编码页(表)

        object[] bytes = CreateRegionCode(4);//生4个随机中文汉字编码

        string[] str = new string[4];

        System.Text.StringBuilder sb = new System.Text.StringBuilder();

        for (int i = 0; i < 4; i++)

        {

            //根据汉字编码的字节数组解码出中文汉字

            str[i] = gb.GetString((byte[])Convert.ChangeType(bytes[i], typeof(byte[])));

            sb.Append(str[i].ToString());

        }

        return sb.ToString();

    }

    /// <summary>

    /// 产生随机中文字符

    /// </summary>

    /// <param name="strlength"></param>

    /// <returns></returns>

    private static object[] CreateRegionCode(int strlength)

    {

        //定义一个字符串数组储存汉字编码的组成元素

        string[] rBase = new String[16] { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

        Random rnd = new Random();

        object[] bytes = new object[strlength];



        for (int i = 0; i < strlength; i++)

        {

            //区位码第1位

            int r1 = rnd.Next(11, 14);

            string str_r1 = rBase[r1].Trim();

            //区位码第2位

            rnd = new Random(r1 * unchecked((int)DateTime.Now.Ticks) + i);

            int r2;

            if (r1 == 13)

            {

                r2 = rnd.Next(0, 7);

            }

            else

            {

                r2 = rnd.Next(0, 16);

            }

            string str_r2 = rBase[r2].Trim();



            //区位码第3位

            rnd = new Random(r2 * unchecked((int)DateTime.Now.Ticks) + i);//更换随机种子

            int r3 = rnd.Next(10, 16);

            string str_r3 = rBase[r3].Trim();



            //区位码第4位

            rnd = new Random(r3 * unchecked((int)DateTime.Now.Ticks) + i);

            int r4;

            if (r3 == 10)

            {

                r4 = rnd.Next(1, 16);

            }

            else if (r3 == 15)

            {

                r4 = rnd.Next(0, 15);

            }

            else

            {

                r4 = rnd.Next(0, 16);

            }

            string str_r4 = rBase[r4].Trim();

            //定义两个字节变量存储产生的随机汉字区位码

            byte byte1 = Convert.ToByte(str_r1 + str_r2, 16);

            byte byte2 = Convert.ToByte(str_r3 + str_r4, 16);



            //将两个字节变量存储在字节数组中

            byte[] str_r = new byte[] { byte1, byte2 };



            //将产生的一个汉字的字节数组放入object数组中

            bytes.SetValue(str_r, i);

        }

        return bytes;

    }

    /// <summary>

    /// 画图片的背景图+干扰线 

    /// </summary>

    /// <param name="checkCode"></param>

    /// <returns></returns>

    private Bitmap CreateImages(string checkCode, string type)

    {

        int step = 0;

        if (type == "ch")

        {

            step = 5;//中文字符,边界值做大

        }

        int iwidth = (int)(checkCode.Length * (13 + step));

        System.Drawing.Bitmap image = new System.Drawing.Bitmap(iwidth, 33);

        Graphics g = Graphics.FromImage(image);

        g.Clear(Color.White);//清除背景色

        Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };//定义随机颜色

        string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" };

        Random rand = new Random();



        for (int i = 0; i < 50; i++)

        {

            int x1 = rand.Next(image.Width);

            int x2 = rand.Next(image.Width);

            int y1 = rand.Next(image.Height);

            int y2 = rand.Next(image.Height);

            g.DrawLine(new Pen(Color.LightGray, 1), x1, y1, x2, y2);//根据坐标画线

        }



        for (int i = 0; i < checkCode.Length; i++)

        {

            int cindex = rand.Next(7);

            int findex = rand.Next(5);



            Font f = new System.Drawing.Font(font[findex], 15, System.Drawing.FontStyle.Bold);

            Brush b = new System.Drawing.SolidBrush(c[cindex]);

            int ii = 4;

            if ((i + 1) % 2 == 0)

            {

                ii = 2;

            }

            g.DrawString(checkCode.Substring(i, 1), f, b, 3 + (i * (12 + step)), ii);



        }

        g.DrawRectangle(new Pen(Color.Black, 0), 0, 0, image.Width - 1, image.Height - 1);

        System.IO.MemoryStream ms = new System.IO.MemoryStream();

        return image;

    }

}

 登录模块设计sidebar.ascx

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="sidebar.ascx.cs" Inherits="Web.UserControl.sidebar" %>

        <div class="bar notice">

                <div class="title ">公告</div>

                <div class="c">

                    <p>第一次登陆请尽快修改密码,默认密码是您生日的后六位</p>

                </div>

            </div>



            <div class="bar login">

                <div class="title">登陆</div>

                <div class="c">

                    <table>

                        <tr>

                            <td style="width: 500px">类  型:</td>

                            <td style="width: 85%">

                                <asp:DropDownList ID="ddl" runat="server">

                                    <asp:ListItem Value="1">学生</asp:ListItem>

                                    <asp:ListItem Value="2">老师</asp:ListItem>

                                </asp:DropDownList>

                            </td>

                        </tr>

                        <tr>

                            <td>账  号:</td>

                            <td>

                                <asp:TextBox ID="txtNo" Width="80" runat="server"></asp:TextBox>

                            </td>

                        </tr>

                        <tr>

                            <td>密  码:</td>

                            <td>

                                <asp:TextBox ID="txtPwd" Width="80" runat="server" TextMode="Password"></asp:TextBox>

                            </td>

                        </tr>

                        <tr>

                            <td>验证码:</td>

                            <td>

                                <asp:TextBox ID="txtCode" style="vertical-align:middle" Width="30" runat="server"></asp:TextBox><img title="看不清?" style=" cursor:pointer ;vertical-align:middle" width="45px" src="../ValidateCode.ashx" onclick="this.src='../ValidateCode.ashx?_='+Math.random()" />

                            </td>

                        </tr>

                        <tr>

                            <td colspan="2" align="center">

                                <asp:Button ID="btnLogin" runat="server" Text="登  陆" OnClick="btnLogin_Click" />

                                <asp:Label ID="lblMsg" runat="server" ForeColor="Red"></asp:Label>

                            </td>

                        </tr>

                    </table>

                </div>

            </div>

 sidebar.ascx.cs

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;



namespace Web.UserControl

{

    public partial class sidebar : System.Web.UI.UserControl

    {

        protected void Page_Load(object sender, EventArgs e)

        {



        }



        protected void btnLogin_Click(object sender, EventArgs e)

        {



            //学生  1  老师 2

            string type = ddl.SelectedValue;

            string no = txtNo.Text.Trim();

            string pwd = txtPwd.Text.Trim();

            //md5加密

            pwd =   Common.GetMd5(pwd);





            string code = txtCode.Text.Trim();

             

            //验证码正确    因为session有过期失效的问题,

            if (Session["code"] != null &&  code.ToLower() == Session["code"].ToString().ToLower())

            {

                //

                Session.Remove("code");

                string msg;

                //学生

                if (type == "1")

                { //判断用户名密码是否正确

                    ItcastOCSS.BLL.Student bll = new ItcastOCSS.BLL.Student();

                    ItcastOCSS.Model.Student stu = new ItcastOCSS.Model.Student();

                    if (bll.Login(no, pwd, out msg, out stu))

                    {

                        //记录登陆成功的状态

                        Session["user"] = stu;

                        //跳转

                        Response.Redirect("Student/Index.aspx");

                    }

                    lblMsg.Text = msg;

                }

                else if (type == "2")

                { 

                    //老师

                    ItcastOCSS.BLL.Teacher bll = new ItcastOCSS.BLL.Teacher();

                    ItcastOCSS.Model.Teacher tea = new ItcastOCSS.Model.Teacher();

                    if (bll.Login(no, pwd, out msg, out tea))

                    {

                        Session["user"] = tea;

                        //跳转

                        if (tea.TIsAdmin == 1)

                        {

                            //管理员

                            Response.Redirect("Admin/Index.aspx");

                        }

                        else if(tea.TIsAdmin == 0)

                        { 

                            //老师

                            Response.Redirect("Teacher/Index.aspx");

                        }

                    }

                }

                

            }

            else

            { 

                //验证码错误

                lblMsg.Text = "验证码错误";

            }

            

        }

    }

}

  testMd5.aspx   md5加密,只有后台代码,前台什么都不用写

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Security.Cryptography;

using System.Text;

namespace Web

{

    public partial class testMd5 : System.Web.UI.Page

    {

        protected void Page_Load(object sender, EventArgs e)

        {

            Response.Write(GetMd5("admin"));

        }



        private string GetMd5(string str)

        {

            //把字符串转换成字节数组

            byte[] buffer = Encoding.Default.GetBytes(str);



            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

            //md5加密

            byte[] cryptBuffer =  md5.ComputeHash(buffer);

            string s = "";

            //把每一个字节 0-255,转换成两位16进制数     

            for (int i = 0; i < cryptBuffer.Length; i++)

            {

                s += cryptBuffer[i].ToString("X2");

            }

            return s;

        }

    }

}

 

 

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