带有背景噪音线的验证码

   写登陆界面时,少不了要写验证码,下面是我整理的生成数字字母混合随机验证码并带有背景噪音线的。net代码。

  首先,建立一个名为VerifyImage.aspx的web窗体,后台编写如下代码。

 

using System;
using System.Collections;
using System.Configuration;
using System.Data;
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.Drawing;
public partial class Login_VerifyImage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string Figure = Request.QueryString["pNum"].ToString();
        int pW = 70;
        int pH = 22;
        System.IO.MemoryStream ms = new System.IO.MemoryStream();
        ms = GetImg(Figure, pW, pH);
        Response.ClearContent();
        Response.ContentType = "Last/Gif";
        Response.BinaryWrite(ms.ToArray());
    }
   
    /// <summary>
    /// 生成图像并获取二进制信息
    /// </summary>
    /// <param name="Figure">验证码字符串</param>
    /// <param name="Width">图像宽度</param>
    /// <param name="Height">图像高度</param>
    /// <returns></returns>
    public System.IO.MemoryStream GetImg(string Figure, int Width, int Height)
    {
        System.Drawing.Bitmap Last = new System.Drawing.Bitmap(Width, Height);
        Graphics g = Graphics.FromImage(Last);
        try
        {
            //生成随机生成器
            Random random = new Random();
            //清空图片背景色
            g.Clear(Color.White);
            //画图片的背景噪音线
            for (int i = 0; i < 8; i++)
            {
                int x1 = random.Next(Last.Width);
                int x2 = random.Next(Last.Width);
                int y1 = random.Next(Last.Height);
                int y2 = random.Next(Last.Height);
                g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
            }
            Font font = new System.Drawing.Font("宋体", 15, (System.Drawing.FontStyle.Bold));
            System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, Last.Width, Last.Height), Color.Black, Color.DarkBlue, 1.2f, true);
            g.DrawString(Figure, font, brush, 5, 2);

            //画图片的前景噪音点
            for (int i = 0; i < 100; i++)
            {
                int x = random.Next(Last.Width);
                int y = random.Next(Last.Height);
                Last.SetPixel(x, y, Color.FromArgb(random.Next()));
            }
            //画图片的边框线
            g.DrawRectangle(new Pen(Color.Silver), 0, 0, Last.Width - 1, Last.Height - 1);
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            Last.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
            return ms;
        }
        finally
        {
            g.Dispose();
            Last.Dispose();
        }
    }
}

 

然后,新名为建一个Login.aspx的登陆页面,拖拽一个img控件,一个textBox控件,一个button控件和一个LinkButton控件,Html代码如下:

html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    验证码:<img ID="MyImage" style="vertical-align:top" height="22" width="70" runat="server" />
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:Button ID="Button1" runat="server" Text="验证" onclick="Button1_Click" />
        <asp:LinkButton ID="LinkButton1" runat="server" onclick="LinkButton1_Click">看不清,换一张?</asp:LinkButton>
    </div>
    </form>
</body>
</html>

,后天编写生成随机位数及验证码验证是否正确。

 

using System;
using System.Collections;
using System.Configuration;
using System.Data;
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;

public partial class Login_LoginForm : System.Web.UI.Page
{
    private static string strNum;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            strNum = CreateFigure(4);
            MyImage.Src = "VerifyImage.aspx?pNum=" + strNum + "";
        }
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        if (TextBox1.Text.Equals(strNum))
        {
            //校验码正确
        }
        else
        {
            Response.Write("校验码不正确");
        }
    }
    /// <summary>
    /// 产生随即验证码
    /// </summary>
    /// <param name="BitNum">验证码位数</param>
    /// <returns></returns>
    public string CreateFigure(int BitNum)
    {
        string Base = "123456789abcdefghjklmnpqrstuvwxyz";
        Random Rm = new Random();
        string Figure = "";
        for (int i = 0; i < BitNum; i++)
        {
            int m = Rm.Next(0, Base.Length - 1);
            Figure += Base.Substring(m, 1);
        }
        return Figure;
    }
    protected void LinkButton1_Click(object sender, EventArgs e)
    {
        strNum = CreateFigure(4);
        MyImage.Src = "VerifyImage.aspx?pNum=" + strNum + "";
    }
}

 

posted @ 2013-04-18 20:12  丫丫是个小码农  阅读(1043)  评论(7编辑  收藏  举报