imagehandler.ashx

《圣殿祭司的ASP.NET 2.0开发详解——使用C#》光盘内容.包含了书籍所含的源代码.非常经典的一本asp.net2.0的书籍

<%@ WebHandler Language="C#" Class="ImageHandler" %>

using System;
using System.Web;
using System.IO;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;

public class ImageHandler : IHttpHandler {
    
    public void ProcessRequest (HttpContext context) 
    {
        //创建Bitmap
        Bitmap imageTime = new Bitmap(500, 100);

        //从Bitmap取得Image
        Graphics g = Graphics.FromImage(imageTime);

        //将Bitmap背景色填满LightPink颜色
        SolidBrush colorPen = new SolidBrush(Color.White);
        g.FillRectangle(colorPen, 0, 0, 500, 800);
        
        //定义画笔及样式
        //取得HatchStyle列举类型的所有成员
        Array obj = Enum.GetValues(typeof(HatchStyle));
        int valueStyle = new Random().Next(obj.Length);
        HatchStyle brushStyle = (HatchStyle)obj.GetValue(valueStyle);
        HatchBrush theBrush = new HatchBrush(brushStyle, Color.White, Color.Black);

        //在Bitmap上绘制GDI+时间字体
        g.DrawString(DateTime.Now.ToLongTimeString(), new Font("Arial Black", 48), theBrush, 0, 0);

        //建立MemoryStream
        MemoryStream ms = new MemoryStream();
        //将BitMap存入MemoryStream
        imageTime.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
        //新建二进位的Byte数组
        byte[] buffer = new byte[ms.Length];
        ms.Seek(0, SeekOrigin.Begin);
        //将数据写入到buffer之中
        ms.Read(buffer, 0, (int)ms.Length);
        ms.Close();
        //将buffer输出成数据流
        context.Response.OutputStream.Write(buffer, 0, buffer.Length);
        //关闭数据流
        context.Response.OutputStream.Close();

        buffer = null;
        imageTime.Dispose();
        g.Dispose();
    }
 
    public bool IsReusable 
    {
        get 
        {
            return false;
        }
    }
}