ASP.NET筆記之 Httphandler的操作詳解

1、httphandler

執行個體1：通過產生一張動態圖片輸出用戶端的IP地址、作業系統類型、瀏覽器類型

複製代碼 代碼如下:<%@ WebHandler Language="C#" Class="visitor" %>

using System;
using System.Web;

public class visitor : IHttpHandler {

public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "image/JPEG";
using (System.Drawing.Bitmap bitImage = new System.Drawing.Bitmap(330, 300))
{
//設定畫布
using (System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitImage))
{
//IP
g.DrawString("IP:" + context.Request.UserHostAddress, new System.Drawing.Font("宋體", 20), System.Drawing.Brushes.Red, new System.Drawing.PointF(0, 0));
//作業系統
g.DrawString("作業系統:" + context.Request.Browser.Platform, new System.Drawing.Font("宋體", 20), System.Drawing.Brushes.Red, new System.Drawing.PointF(0, 50));
//瀏覽器
g.DrawString("瀏覽器:" + context.Request.Browser.Type, new System.Drawing.Font("宋體", 20), System.Drawing.Brushes.Red, new System.Drawing.PointF(0, 100));
}
//儲存到輸出資料流中
bitImage.Save(context.Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);

}
}

public bool IsReusable {
get {
return false;
}
}

}

執行個體2：通過“下載”串連，彈出使用者附件儲存

html代碼：<a href="dowload.ashx">下載</a>

複製代碼 代碼如下:<%@ WebHandler Language="C#" Class="dowload" %>

using System;
using System.Web;

public class dowload : IHttpHandler {

public void ProcessRequest(HttpContext context)
{
string fileName = HttpUtility.UrlEncode("悲劇.jpg");
context.Response.ContentType = "image/JPEG";

//開啟附件對話方塊 報文頭header和設定它的值
context.Response.AddHeader("Content-Disposition", "attachment:filename=" + fileName);
context.Response.WriteFile("蘋果.jpg");
}

public bool IsReusable {
get {
return false;
}
}

}