验证码

开发工具与关键技术：VS   ,   ASP.NET.MVC;

作者：吴维杰

撰写时间：2019.06.05

控制器部分:

public ActionResult ValideCode()

           1.{string strValideCode = Common.ValidCodeUtils.GetRandomCode(5);

           2. Session["ValideCode"] = strValideCode.Trim();

           3. byte[] imgByte = Common.ValidCodeUtils.CreateImage(strValideCode);

           4.return File(imgByte, @"image/jpeg");}

  1.调用封装好的方法生成5位数随机字符串

  2.将生成的字符串保存到session中

  3.将生成的字符串转换成图片

  4.将生成的图片返回到浏览器

封装的实体类方法:

   1. public static string GetRandomCode(int intLength)

        {/*产生数字和密码混合的随机数*/

            string strReturn = string.Empty;

            Random random = new Random();//随机数

            for (int i = 0; i < intLength; i++)

            {char cRerult;

                int intRandom = random.Next();//产生一个非负随机整数

                /*根据当前随机数来确定字符串*/

                //intRandom % 3 获取的是intRandom/3 得到的余数

                if (intRandom % 3 == 0)

                {//产生数字//位数来产生数字

                    cRerult = (char)(0x30 + (intRandom % 10));}

                else if (intRandom % 3 == 1)

                { //位数产生大写字母:大写字符 65-97 A 65

                    //68 D  25 Z

                    cRerult = (char)(0x41 + (intRandom % 0x1a)); }else

                {/余数为2//产生小写字母 98-116

                 cRerult = (char)(0x61 + (intRandom % 0x1a)); }

                strReturn += cRerult.ToString();}

return strReturn; }

     2. public static byte[] CreateImage(string strRandom)

        {//新增图片

            Bitmap newBitmap = new Bitmap(strRandom.Length * 20, 30);

            Graphics g = Graphics.FromImage(newBitmap);

            g.Clear(Color.White);

            //在图片上绘制文字

            SolidBrush solidBrush = new SolidBrush(Color.Red);

            g.DrawString(strRandom, new Font("Aril", 17), solidBrush, 12, 1);

            //在图片上绘制干扰线(这里可以绘制其它类型的干扰)

            Random random = new Random();

            for (int i = 0; i < 10; i++)(利用for循环绘制多条线)

            {//产生一条线，并绘制到画布。 起始点（x,y）  总结点

                int x1 = random.Next(newBitmap.Width);

                int y1 = random.Next(newBitmap.Height);

                int x2 = random.Next(newBitmap.Width);

                int y2 = random.Next(newBitmap.Height);

                g.DrawLine(new Pen(Color.DarkGray), x1, y1, x2, y2); }

            //绘制图片的前景干扰点

            for (int i = 0; i < 100; i++){

                int x = random.Next(newBitmap.Width);

                int y = random.Next(newBitmap.Height);

                newBitmap.SetPixel(x, y, Color.FromArgb(random.Next()));}

            //在最外边绘制边框

g.DrawRectangle(new Pen(Color.Blue), 0, 0, newBitmap.Width, newBitmap.Height);

g.DrawRectangle(new Pen(Color.Blue), -1, -1, newBitmap.Width, newBitmap.Height);

            //将图转保存到内存流中

            MemoryStream ms = new MemoryStream();

            newBitmap.Save(ms, ImageFormat.Jpeg);

            return ms.ToArray();//将流内容写入byte数组返回}

页面部分:

//点击验证码图片，切换验证码,加上参数ts，解决浏览器缓存问题

$("#vcImg").click(function () {

            $("#vcImg").attr("src", "/Main/ValideCode?ts="+new Date().getTime());});

        //验证登录

        $("#btnSubmit").click(function () {

            //序列化表单

            var dataForm = $("#fmLogin").serializeArray();

           //提交数据

            $.post("/Main/CheckLogin", dataForm, function (msg) {

                if (msg == "success") {window.location.href = "/Main/Main";}

                else {layer.alert(msg, {icon:0,title:"提示"});}

                //清空验证码文本框&密码

                $("#PassWord").val("");$("#VerificationCode").val("");

                //刷新验证码 $("#vcImg").click();});});

效果图: