一.说明
此文是小白在学习张晨光老师的视频教学<< WEB服务器编程技术>>中做的学习笔记,一些知识点也是跟着教程走的,大家也可以去老师的主页去学习,谢谢大家.
二.生成验证码图片(CodeHandler.ashx)
上一节,我们使用的是checkcode.aspx.cs来处理生成验证码图片,今天我们在Handler文件夹下创建一般处理程序CodeHandler.ashx,来代替.代码如下:
using System;using System.Collections.Generic;using System.Drawing;using System.Drawing.Imaging;using System.IO;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.SessionState;namespace MyMusci.Handler{/// <summary>/// CodeHandler 的摘要说明/// </summary>public class CodeHandler : IHttpHandler, IRequiresSessionState{public void ProcessRequest(HttpContext context){context.Response.ContentType = "text/plain";string chkCode = string.Empty;int ix, iy;ix = 140;iy = 40;//颜色列表，用于验证码、噪线、噪点 Color[] color = {Color.Black, Color.Red, Color.Blue, Color.Green, Color.Orange, Color.Brown, Color.Brown, Color.DarkBlue };//字体列表，用于验证码 string[] font = {"Times New Roman", "MS Mincho", "Book Antiqua", "Gungsuh", "MingLiU", "Arial" };//验证码的字符集，去掉了一些容易混淆的字符 char[] character = {'2', '3', '4', '5', '6', '8', '9', '0', '1', '小', '白' };Random rnd = new Random();//生成验证码字符串 for (int i = 0; i < 4; i++){chkCode += character[rnd.Next(character.Length)];}Bitmap bmp = new Bitmap(ix, iy);Graphics g = Graphics.FromImage(bmp);g.Clear(Color.White);//画噪线 for (int i = 0; i < 10; i++){int x1 = rnd.Next(ix);int y1 = rnd.Next(iy);int x2 = rnd.Next(ix);int y2 = rnd.Next(iy);Color clr = color[rnd.Next(color.Length)];g.DrawLine(new Pen(clr), x1, y1, x2, y2);}//画验证码字符串 for (int i = 0; i < chkCode.Length; i++){string fnt = font[rnd.Next(font.Length)];Font ft = new Font(fnt, iy/2, FontStyle.Bold);Color clr = color[rnd.Next(color.Length)];g.DrawString(chkCode[i].ToString(), ft, new SolidBrush(clr), (float)i * 30 + 2, (float)2);}//画噪点 for (int i = 0; i < 50; i++){int x = rnd.Next(bmp.Width);int y = rnd.Next(bmp.Height);Color clr = color[rnd.Next(color.Length)];bmp.SetPixel(x, y, clr);}//将验证码写入SESSION,为什么第二个页面没法获取值？？？//一般处理程序增加接口文件;HttpContext.Current.Session["Code"] = chkCode.ToUpper();//清除该页输出缓存，设置该页无缓存 context.Response.Buffer = true;context.Response.ExpiresAbsolute = System.DateTime.Now.AddMilliseconds(0);context.Response.Expires = 0;context.Response.CacheControl = "no-cache";context.Response.AppendHeader("Pragma", "No-Cache");//将验证码图片写入内存流，并将其以 "image/Png" 格式输出 //我这个页面返回的是图片;MemoryStream ms = new MemoryStream();try{bmp.Save(ms, ImageFormat.Png);context.Response.ClearContent();context.Response.ContentType = "image/Png";context.Response.BinaryWrite(ms.ToArray());}finally{//显式释放资源 bmp.Dispose();g.Dispose();}}public bool IsReusable{get{return false;}}}}
三.登录页面添加验证码(login_new.aspx)
因为我们更换了验证码的生成程序,所以也要在登录界面更换对应代码:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="login_new.aspx.cs" Inherits="MyMusci.login_new" %><!DOCTYPE html><html xmlns="/1999/xhtml"><head runat="server"><meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title><link href="bootstrap-5.1.3-dist/css/bootstrap.css" rel="stylesheet" /><script src="bootstrap-5.1.3-dist/js/bootstrap.bundle.js"></script><script src="js/jquery.js"></script><style>/*将整个登入的div垂直居中*/.all {width: 700px;height: 260px;background-color: rgba(205,197,191,0.8);position: absolute;top: 0;bottom: 0;left: 0;right: 0;margin: auto;padding:0;}body {background-image: url("img/dm.jpg");/*整个图片作为背景，不够自动拉伸*/background-size: cover;}</style></head><body><form id="form1" runat="server"><div class="container mt-3"><asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager><asp:UpdatePanel ID="UpdatePanel1" runat="server"><ContentTemplate><table class="table all"><tr><td class="table-primary display-3 text-center text-primary" colspan="3">登录界面</td></tr><tr><td>账户</td><td><asp:TextBox ID="userName" runat="server"></asp:TextBox></td><td><asp:RequiredFieldValidator ID="rfv_useName" runat="server" ControlToValidate="userName" Display="Dynamic" ErrorMessage="RequiredFieldValidator" ForeColor="Red">账户不可为空</asp:RequiredFieldValidator><asp:RegularExpressionValidator ID="rev_userName" runat="server" ControlToValidate="userName" Display="Dynamic" ErrorMessage="RegularExpressionValidator" ForeColor="Red" ValidationExpression="\w{5,13}">您输入的账户异常(5-12位)</asp:RegularExpressionValidator></td></tr><tr><td class="auto-style2">密码</td><td class="auto-style2"><asp:TextBox ID="userPwd" runat="server"></asp:TextBox></td><td class="auto-style2"><asp:RequiredFieldValidator ID="rfv_userPwd" runat="server" ControlToValidate="userPwd" Display="Dynamic" ErrorMessage="RequiredFieldValidator" ForeColor="Red">密码不可为空</asp:RequiredFieldValidator><asp:RegularExpressionValidator ID="rev_userPwd" runat="server" ControlToValidate="userPwd" Display="Dynamic" ErrorMessage="RegularExpressionValidator" ForeColor="Red" ValidationExpression="\w{8,13}">您输入的密码异常(8位)</asp:RegularExpressionValidator></td></tr><tr><td>验证码</td><td><asp:TextBox ID="code" runat="server"></asp:TextBox></td><td><img id="imgcode" src="Handler/CodeHandler.ashx" /><asp:Label ID="codeText" runat="server" Text=""></asp:Label></td></tr><tr><td><asp:Button ID="btn_sub" runat="server" class="btn btn-primary" OnClick="btn_sub_Click" Text="登录" /></td><td><asp:LinkButton ID="LinkButton1" runat="server" class="btn btn-secondary" PostBackUrl="~/RegUser.aspx" CausesValidation="False">注册</asp:LinkButton></td><td> </td></tr></table></ContentTemplate></asp:UpdatePanel></div></form><script>//图片点击事件$("#imgcode").click(function () {$("#imgcode").attr("src", "Handler/CodeHandler.ashx?t=" + Math.random());})</script></body></html>
后台代码也作对应的代码添加(login_new.aspx.cs):
using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.Data;using System.Collections;namespace MyMusci{public partial class login_new : System.Web.UI.Page{protected void Page_Load(object sender, EventArgs e){}/// <summary>/// 重置按钮点击事件/// </summary>/// <param name="sender"></param>/// <param name="e"></param>protected void btn_reset_Click(object sender, EventArgs e){userName.Text = "";userPwd.Text = "";}/// <summary>/// 登录按钮点击事件/// </summary>/// <param name="sender"></param>/// <param name="e"></param>protected void btn_sub_Click(object sender, EventArgs e){//测试//if ("administrator".Equals(userName.Text) && "12345678".Equals(userPwd.Text)) {// Response.Redirect("index.aspx");//}//这里判断验证控件是否通过,如果没通过,则返回if (!rev_userName.IsValid || !rev_userPwd.IsValid) {return;}//这里判断用户是否输入了验证码的输入框的值,如果没有输入,提示用户,并返回if (code.Text != Session["Code"].ToString()){codeText.Text = "验证码不正确,请重新输入";return;}//否则清空提示值,并且让代码正常运行下去else {codeText.Text = "";}string sql = "SELECT COUNT(*) FROM user_all WHERE user_name=?name AND user_pwd=?pwd";Hashtable ht = new Hashtable();ht.Add("name", userName.Text.ToString());ht.Add("pwd", ChangPwd.UserMd5(userPwd.Text.ToString()));int resilc = ToolMysqlDate.excutScal(sql, ht);if (resilc > 0){//将用户名绑定到SessionSession["userName"] = userName.Text.ToString();//Response是服务器发出的响应,耗费资源,服务器的内存和网络的带宽//Response.Redirect("index.aspx");ScriptManager.RegisterStartupScript(UpdatePanel1, typeof(UpdatePanel), "ok_login", "alert('您已成功登录!');location.href='index.aspx'", true);}else{//Response.Write("<script>alert('您输入的账户或密码有误,请核对后输入!!!')</script>");ScriptManager.RegisterStartupScript(UpdatePanel1, typeof(UpdatePanel), "error_login", "alert('您输入的账户或密码有误,请核对后输入!!!')", true);}}}}
四.效果
当验证通过,且验证码正确时:
当验证码不正确时:
