首页 > 代码库 > JS+ASP.NET 图片验证码
JS+ASP.NET 图片验证码
图片验证码控件
<img id="imgYZM" src=http://www.mamicode.com/"CheckCode.aspx" onm ouseup="RefreshCheckImage()" alt="点击重新获取" />
点击再次获取验证码
function RefreshCheckImage() { var el = document.getElementById("imgYZM"); el.src = http://www.mamicode.com/el.src + '?'; //这个即为再次访问,刷新验证码>
CheckCode.aspx 页面生成验证码/// <summary> /// 生成验证码,写入Session["CheckCode"] /// </summary> public partial class CheckCode : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { this.CreateCheckCodeImage(RndNum()); } private string RndNum() { int number; char code; string checkCode = String.Empty; 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(); } Session["CheckCode"] = checkCode; //Response.Cookies.Add(new HttpCookie("checkcode", checkCode)); return checkCode; } private void CreateCheckCodeImage(string checkCode) { if (checkCode == null || checkCode.Trim() == String.Empty) return; Bitmap image = new 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("Arial", 12, (FontStyle.Bold | FontStyle.Italic)); //System.Drawing.Drawing2D LinearGradientBrush brush = new 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(); } } }
JS+ASP.NET 图片验证码
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。