求救

Question

用asp。net 在登录界面界怎么样写代码 才会有出现验证码那个功能呢？
还有怎样把那日期的控件弄成你一点那个三角符才出现日期控件

Answer 1

2：找第三方控件1：新建一个aspx页面，page_load里写入以下内容
    protected void Page_Load(object sender, EventArgs e)
    {
        Response.Buffer = true;
        Response.ExpiresAbsolute = DateTime.Now.AddDays(-1);
        Response.Expires = 0;
        Response.CacheControl = "no-cache";
        Response.AddHeader("Pragma", "No-Cache");        System.Random rdm = new Random();
        Bitmap bp = new Bitmap(100, 40);
        string AllStr = "23456789ABCDEFGHJKMNPQRSTUVWXYZabcdefghjkmnpqrstuvwxyz";
        string[] zt = new string[] { "Arial Black", "Comic Sans MS", "Georgia" };
        SolidBrush bs = new SolidBrush(Color.FromArgb(255, 55, 0));
        SolidBrush bs1 = new SolidBrush(Color.FromArgb(243, 241, 241));
        SolidBrush bs2 = new SolidBrush(Color.FromArgb(80, 230, 115, 0));
        Graphics Dr = Graphics.FromImage(bp);
        Dr.FillRectangle(bs1, 0, 0, 100, 40);
        string rr = "";
        for (int i = 0; i <= 30; i++)
        {
            char c1 = AllStr[rdm.Next(0, AllStr.Length - 1)];
            Dr.DrawString(c1.ToString(), new Font(zt[rdm.Next(0, zt.Length - 1)], (float)rdm.Next(12, 22)), bs2, rdm.Next(0, 100) - 20, rdm.Next(0, 40) - 15);
        }
        Dr.DrawLine(new Pen(Color.FromArgb(100, Color.Red)), 0, rdm.Next(0, 40), 100, rdm.Next(0, 40));
        Dr.DrawLine(new Pen(Color.FromArgb(100, Color.Red)), 0, rdm.Next(0, 40), 100, rdm.Next(0, 40));
        for (int i = 0; i < 4; i++)
        {
            char c1 = AllStr[rdm.Next(0, AllStr.Length - 1)];
            rr += c1;
            Dr.DrawString(c1.ToString(), new Font(zt[rdm.Next(0, zt.Length - 1)], (float)rdm.Next(12, 22)), bs, i * 25, rdm.Next(0, 7));
        }
        Dr.DrawLine(new Pen(Color.FromArgb(100, Color.Red)), rdm.Next(0, 100), 0, rdm.Next(0, 100), 40);
        for (int i = 0; i <= 160; i++)
            bp.SetPixel(rdm.Next(0, 100), rdm.Next(0, 40), Color.FromArgb(rdm.Next(0, 255), rdm.Next(0, 255), rdm.Next(0, 255)));        Session["ValidateCode"] = rr;
        bp.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);
        Response.Flush();
        Response.End();
    }
用一个image控件，imageurl=你的这个aspx页面
如果刷几次出现同样的图片，那么在url后面+"?t="+DateTime.Now.Tick.ToString()
验证的时候判断Session["ValidateCode"] 和用户输入的是否相等。

Answer 2

<asp:textbox id="txtLZM" runat="server" Width="144px" CssClass="inputText" Height="14px"></asp:textbox>
<asp:label id="Lbl" runat="server" Width="38px">
<IMG src="CheckCode.aspx" align="absmiddle"></asp:label> protected void btnSubmit_Click(object sender, EventArgs e)
    {
        if (Page.IsValid)
        {
            if (Session["ValidateCode"] == null)
            {
                return;
            }
            if (Session["ValidateCode"].ToString().Equals(this.txtLZM.Text.Trim()))
            {
                if (string.IsNullOrEmpty(this.txtUser.Text))
                {
                  ClientScript.RegisterStartupScript(this.GetType(), "message", "<script language='javascript' defer>alert('请输入用户名');</script>");
                    return;
                }
                //查询用户
                DataSet ds;
                DataRowCollection myrows = ds.Tables[0].Rows;
                if (myrows.Count == 0)
                {  ClientScript.RegisterStartupScript(this.GetType(), "message", "<script language='javascript' defer>alert('您没有任何权限');</script>");
                    return;
                }
                else
                {
                    if (myrows[0]["kl"].ToString().Trim().Equals(this.txtPwd.Text.Trim().Replace("'", "''")))
                    {  ClientScript.RegisterStartupScript(this.GetType(), "message", "<script language='javascript' defer>alert('您输入的密码不对');</script>");
                    return;
                    }
                    else
                    {
                      this.Response.Write("<script language='javascript'>window.open('main.htm','_self')</script>");
                    }
                }
            }
        }
    }        private string MakeString()
        {
            string validatestr="";
            char ch;
            Random rdom=new Random();
            int n;            for(int i=0;i<4;i++)
            {
                n=rdom.Next();
                if(n%2==0)
                    ch=(char)('0'+(n%10));
                else
                    ch=(char)('A'+(n%26));
                validatestr +=ch.ToString();
            }
            Session["ValidateCode"]=validatestr;
            return validatestr;
        }
        private void GenerateImage(string checkCode)
        {
            Bitmap image=new Bitmap(checkCode.Length*18,30);
            Graphics g= Graphics.FromImage(image);
            try
            {
                Random random = new Random();
                g.Clear(Color.White);
                for(int i=0; i<25; i++)
                {
                    int x1 = random.Next(image.Width);
                    int x2 = random.Next(image.Width);
                    int y1 = random.Next(image.Height);
                    int y2 = random.Next(image.Height);                    g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
                }                Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
                System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
                g.DrawString(checkCode, font, brush, 2, 2);
                for(int i=0; i<100; i++)
                {
                    int x = random.Next(image.Width);
                    int y = random.Next(image.Height);                    image.SetPixel(x, y, Color.FromArgb(random.Next()));
                }
                g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
                Response.ClearContent();
                Response.ContentType = "image/Gif";
                Response.BinaryWrite(ms.ToArray());
            }
            finally
            {
                g.Dispose();
                image.Dispose();
            }日期控件可使用My97DatePicker等

Answer 3

这类代码网上很多呢~  就搜索asp.net 验证码