ASP.NET中图片显示方法实例

本文实例讲述了ASP.NET中图片的显示方法。分享给大家供大家参考。具体如下：

genimage.ashx：
复制代码代码如下:<%@ WebHandler Language="C#" Class="netpix.ImageGenerator" %>

genimage.ashx.cs：

// Copyright （C） 2003 by Greg Ennis// （mailto:greg@ennis.net）//// The contents of this file are subject to the Artistic License （the "License"）.// You may not use this file except in compliance with the License. // You may obtain a copy of the License at:// http://www.opensource.org/licenses/artistic-license.htmlusing System;using System.Collections;using System.ComponentModel;using System.Data;using System.Data.SqlClient;using System.Drawing;using System.Web;using System.IO;using System.Configuration;using System.Web.SessionState;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.HtmlControls;namespace netpix{public class ImageGenerator : IHttpHandler { public bool IsReusable { get { return true; } } public void ProcessRequest（HttpContext Context） { // Get the image filename and album root path from the database//图片浏览次数int numviews;//图片数据库中的IDint picid = Convert.ToInt32（Context.Request["id"]）;//图片路径 string imgpath = npdata.GetPathToPicture（picid, out numviews）;// Writing an image to output streamContext.Response.ContentType = "image/jpg";// "thumbnail" means we are requesting a thumbnail//显示缩略图if （Context.Request["thumbnail"] ！= null）{// Need to load the image, resize it, and stream to the client.// Calculate the scale so as not to stretch or distort the image.Bitmap bmp = new Bitmap（imgpath）;float scale = 150.0f / System.Math.Max（bmp.Height, bmp.Width）;System.Drawing.Image thumb = bmp.GetThumbnailImage（（int）（bmp.Width * scale）, （int）（bmp.Height * scale）, null, System.IntPtr.Zero）;thumb.Save（Context.Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg）;bmp.Dispose（）;thumb.Dispose（）;}else{// Stream directly from the file// Get the stream and send it out the responseSystem.IO.FileStream fs = File.Open（imgpath, FileMode.Open, FileAccess.Read, FileShare.Read）;const int byteLength = 8192;byte[] bytes = new byte[byteLength];while（ fs.Read（bytes, 0, byteLength ） ！= 0 ）{Context.Response.BinaryWrite（bytes）; }fs.Close（）;//更新数据库浏览次数npdata.SetNumViews（picid, numviews+1）;}}}}

使用方法：
复制代码代码如下:imgCtrl.ImageUrl = "genimage.ashx?id=" + Request["id"];

希望本文所述对大家的ASP.NET程序设计有所帮助。