Question

ASP.NET验证码我做完了，如何在主页中验证登陆

验证码后台代码如下
public partial class checkcode : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
CreateCheckCodeImage(GenerateCheckCode());
}

private string GenerateCheckCode()
{
int number;
char code;
string checkCode = String.Empty;
System.Random random = new Random();

for (int i = 0; i < 4; i++)
{
number = random.Next();

if (number % 2 == 0)
code = (char)('0' + (char)(number % 10));
else
code = (char)('A' + (char)(number % 26));

checkCode += code.ToString();
}
Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));
return checkCode;
}

private void CreateCheckCodeImage(string checkCode)
{
if (checkCode == null || checkCode.Trim() == String.Empty)
return;
System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
Graphics g = Graphics.FromImage(image);
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 < 2; 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.Black), 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);
//画图片的前景噪音点
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()));
}
//画图片的边框线
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();
}
}
}
前面就是登陆框，如何使文本框的值与之判断
有人说用session取出，这个用的cookie。如何在前台验证，我怎么验证不了啊？

Answer 1

用cookie和session都可以,不过还是用session好点儿,因为有的电脑可能会限制cookie.

改成session,把下面这句
Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));
替换成
Session.Add("CheckCode",checkCode);

然后在你的登录按钮中比较
if (Check.Text == Session["CheckCode"].ToString())
{
登录代码...
}

Answer 2

Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));
这句已经把验证码写入到Cookies里面了
在验证的登录页面只需把该值取出，验证是否与你输入的相等即可

if（ Request.Cookies["CheckCode"].ToString()==TextBox1.Text）
{
//验证成功
}

Answer 3

我刚做完验证码，用Session判，
在后台的Page_Lode里写Session[checkCode]=checkCode；

前台判断处写
if (this.txtCode.Text.Equals(Session["checkCode"]))
{
.....
}
才做完的绝对没问题！