无法保存验证码的状态,页面提交时验证码又恢复到开始的数字.

[hongqi91101]

<IMG id=authcode_img title=看不清楚？点击换一个！ style="CURSOR: pointer"
onclick="return changeAuthCode();" alt=看不清楚？点击换一个！
src= "validateCode.aspx">


function changeAuthCode() {
var num = new Date().getTime();
var rand = Math.round(Math.random() * 10000);
num = num + rand;
//getObject("authcode_img").src = "authCode.php?tag=" + num;
document.getElementById("authcode_img").src = "validateCode.aspx?tag=" + num;
document.getElementById("identifier").value = num;

return false;
}

页面提交时验证码又恢复到开始的数字.

[hongqi91101]

如何保证提交页面时还是变换后的图片呢!

[acol]

验证码代码

 private static string GenerateCheckCode()
        {
            #region
            int number;
            char code;
            string checkCode = String.Empty;

            System.Random random = new Random();

            for (int i = 0; i < 5; i++)
            {
                number = random.Next();

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

                checkCode += code.ToString();
            }

            HttpContext.Current.Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));

            return checkCode;
            #endregion
        }
        /// <summary>
        /// 生成验证码图片
        /// </summary>
        public static void CreateCheckCodeImage()
        {
            #region
            string checkCode = GenerateCheckCode();
            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 < 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(""宋体"", 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.HotPink, 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);
                HttpContext.Current.Response.ClearContent();
                HttpContext.Current.Response.ContentType = "image/Gif";
                HttpContext.Current.Response.BinaryWrite(ms.ToArray());
            }
            finally
            {
                g.Dispose();
                image.Dispose();
            }
            #endregion
        }
        /// <summary>
        /// 判断用户输入的验证码是否正确
        /// </summary>
        /// <param name="code">验证码</param>
        /// <returns>正确返回TRUE,错误返回FALSH</returns>
        public static bool checkCode(string code)
        {
            #region
            if (System.Web.HttpContext.Current.Request.Cookies["CheckCode"] == null)
                return false;
            else if (System.Web.HttpContext.Current.Request.Cookies["CheckCode"].Value.ToString().ToLower() != code.ToString().ToLower())
                return false;
            else if (System.Web.HttpContext.Current.Request.Cookies["CheckCode"].Value.ToString().ToLower() == code.ToString().ToLower())
                return true;
            else
                return false;
            #endregion
        }

[acol]

生成图片页面

  protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            if (Request.QueryString["refrush"] == "1")
            {
                Response.Redirect(Request.Url.ToString());
              
            }
            else {
                Tools.Security.CreateCheckCodeImage();
            }
        }
        catch
        {
            Tools.Security.CreateCheckCodeImage();
        }
    }

[acol]

protected void Page_Load(object sender, EventArgs e)
{
try
{
if (Request.QueryString["refrush"] == "1")
{
Response.Redirect(Request.Url.ToString());

}
else {
CreateCheckCodeImage();
}
}
catch
{
CreateCheckCodeImage();
}
}

[syayaya]

protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostback)
{}
}

[acol]

不要if(!IsPostback)
{}

[acol]

不需要if(!IsPostback)
{}