打开Visual Studio

新建Web窗体

 <div>
            <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
            <asp:Image ID="Image1" runat="server" ImageUrl="Images/1.jeg" />
            <asp:Button ID="Button1" runat="server" Text="提交" OnClick="Button1_Click" />
        </div>

简单做出验证码验证过程。

新建Images文件夹，添加handel类

 public class MyHandles : IHttpHandler,IRequiresSessionState
    {
        //实现接口
        public bool IsReusable => false;

        public void ProcessRequest(HttpContext context)
        {
            //定义一个随机对象
            Random random = new Random();
            //产生随机数
            int a = random.Next(0, 9);
            int b = random.Next(0, 9);
            int c = random.Next(0, 9);
            int d = random.Next(0,9);
            int e = random.Next(0, 9);
            int f = random.Next(0, 9);
            //建立一个Code装随机数
            string code = "";
            code = code + a + b + c + d + c + f;

            context.Session["code"] = code;//将验证码放入Session作用域

            //创建图
            Bitmap bitmap = new Bitmap(120,30);
            Graphics graphics = Graphics.FromImage(bitmap);
            //绘制验证码
            graphics.DrawString(code, new Font("微软雅黑", 12, FontStyle.Bold), Brushes.Red, new Point(2, 2));
            graphics.Flush();

            bitmap.Save(context.Response.OutputStream,ImageFormat.Jpeg);

        }

在相关配置文件中添加

<system.webServer>
    <handlers>
      <add verb="*" name="h1" type="WebApplication4.MyHandles" path="Images/*"/>
    </handlers>
  </system.webServer>

运行代码

完成此案例

本次案例均为本人大二学年的课堂练习

如有雷同，纯属巧合