一般处理程序 —— GDI

 

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _2_9_输出一幅动态创建的图片
{
    class Program
    {
        //GDI:.Net程序中进行绘图的一些类
        static void Main(string[] args)
        {
            using (Bitmap bmp = new Bitmap(500, 500))//创建一个尺寸为500*500的内存图片
            using (Graphics g = Graphics.FromImage(bmp))//得到图片的画布
            {
                g.DrawString("动态创建的图片", new Font(FontFamily.GenericSerif, 30), Brushes.Red, 100, 100);//Font应该被释放
                g.DrawEllipse(Pens.Blue, 100, 100, 100, 100);
                //bmp.Save(@"一幅动态创建的图片.jpg", ImageFormat.Jpeg);//图片保存到输出流  
                using (Stream stream = File.OpenWrite(@"一幅动态创建的图片.jpg"))
                {
                    bmp.Save(stream, ImageFormat.Jpeg);
                }
            }  

        }
    }
}

　　

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Web;

namespace _2_一般处理程序
{
    /// <summary>
    /// 泡妞证 的摘要说明
    /// </summary>
    public class 泡妞证 : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "image/jpeg";
            string name = context.Request["Name"];
            string imgFullPath = context.Server.MapPath("~/PaoNiuZheng.jpg");
            using (Image bmp = Bitmap.FromFile(imgFullPath))//读取一张已有的图片
            using (Graphics g = Graphics.FromImage(bmp))//得到图片的画布
            using (Font font1 = new Font(FontFamily.GenericSerif, 12))
            using (Font font2 = new Font(FontFamily.GenericSerif, 5))
            {
                {
                    g.DrawString(name, font1, Brushes.Black, 125, 220);//Font应该被释放
                    g.DrawString(name, font2, Brushes.Black, 310, 50);//Font应该被释放
                    bmp.Save(context.Response.OutputStream, ImageFormat.Jpeg);//图片保存到输出流
                }
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

　　

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Web;

namespace _2_一般处理程序
{
    /// <summary>
    /// 输出一幅动态创建的图片 的摘要说明
    /// </summary>
    public class 输出一幅动态创建的图片 : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "image/jpeg";
            string name = context.Request["name"];
            //context.Response.Write("Hello World");
            using (Bitmap bmp = new Bitmap(500, 500))//创建一个尺寸为500*500的内存图片
            using (Graphics g = Graphics.FromImage(bmp))//得到图片的画布
            {
                g.DrawString(name, new Font(FontFamily.GenericSerif, 30), Brushes.Red, 100, 100);//Font应该被释放
                g.DrawEllipse(Pens.Blue, 100, 100, 100, 100);
                //bmp.Save(@"一幅动态创建的图片.jpg", ImageFormat.Jpeg);//图片保存到输出流  
                //直接保存到网页输出流中
                bmp.Save(context.Response.OutputStream, ImageFormat.Jpeg);//图片保存到输出流  
            }  
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

　　

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Web;

namespace _2_一般处理程序
{
    /// <summary>
    /// 显示访问者信息 的摘要说明
    /// </summary>
    public class 显示访问者信息 : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "image/jpeg";
            using (Bitmap bmp = new Bitmap(500, 200))//创建一个尺寸为500*500的内存图片
            using (Graphics g = Graphics.FromImage(bmp))//得到图片的画布
            using (Font font = new Font(FontFamily.GenericSerif, 30))
            {
                HttpRequest request = context.Request;
                g.DrawString("IP:" + request.UserHostAddress, font, Brushes.Red, 0, 0);
                g.DrawString("浏览器:" + request.Browser.Browser + request.Browser.Version, font, Brushes.Red, 0, 50);
                g.DrawString("操作系统:" + request.Browser.Platform, font, Brushes.Red, 0, 100);
                bmp.Save(context.Response.OutputStream, ImageFormat.Jpeg);//图片保存到输出流
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

　　

验证码：

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    <title>登录</title>
    <script type="text/javascript">
        function RefreshCode()
        {
            var CheckCode = document.getElementById("CheckCode");
            CheckCode.src = "CheckCode.ashx?t="+new Date();
        }
    </script>
</head>
<body>
    <form action="Login.ashx" method="post">
        姓名：<input type="text" name="txtName" />
        密码：<input type="password" name="txtPwd" />
        验证码：<img src="CheckCode.ashx" id="CheckCode" onclick="RefreshCode()" />
        <input type="text" name="txtCode" />
        <input type="submit" name="btnLogin" value="提交" />
        <div style="padding:10px; color:red;">{^msg$}</div>
    </form>
</body>
</html>

　　

 

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Web;

namespace _2_一般处理程序
{
    /// <summary>
    /// 验证码 的摘要说明
    /// </summary>
    public class 验证码 : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            //动态生成一张200*50的图片，显示一个随机的4位数。
            context.Response.ContentType = "image/jpeg";
            using (Bitmap bmp = new Bitmap(200, 50))//创建一个尺寸为500*500的内存图片
            using (Graphics g = Graphics.FromImage(bmp))//得到图片的画布
            using (Font font = new Font(FontFamily.GenericSerif, 30))
            {
                Random rd = new Random();
                string num = " ";
                for (int i = 0; i < 4; i++)
                {
                    num += rd.Next(0,9)+" ";
                }
                HttpRequest request = context.Request;
                g.DrawString(num.ToString(), font, Brushes.Red,30, 0);
                bmp.Save(context.Response.OutputStream, ImageFormat.Jpeg);//图片保存到输出流
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}