ASP.NET实现根据URL生成网页缩略图的方法

来源：互联网发布：南昌淘宝摄影招聘编辑：程序博客网时间：2024/06/05 18:06

这篇文章主要介绍了ASP.NET实现根据URL生成网页缩略图的方法,结合实例较为详细的分析了asp.net生成网页缩略图的详细实现技巧与相关注意事项,需要的朋友可以参考下

本文实例讲述了ASP.NET实现根据URL生成网页缩略图的方法。分享给大家供大家参考，具体如下：

工作中需要用到根据URL生成网页缩略图功能，提前做好准备。

在网上找了份源码，但是有错误:当前线程不在单线程单元中，因此无法实例化 ActiveX 控件“8856f961-340a-11d0-a9”，解决后运行良好，记录在此备用！

起始页：Default.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="CaptureToImage._Default" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" ><head id="Head1" runat="server"> <title>Snap</title></head><body> <form id="form1" runat="server"> <div> <input type="button" onclick="window.open('Snap.aspx?url=www.njude.com.cn')" value="生成网页缩略图"/> </div> </form></body></html>

调用页：Snap.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Snap.aspx.cs" Inherits="CaptureToImage.Snap" AspCompat="true" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" ><head runat="server"> <title>无标题页</title></head><body> <form id="form1" runat="server"> <div> </div> </form></body></html>

PS：红色字体部分是为解决错误增加的代码，强制程序在单线程环境下运行！

调用页：Snap.aspx.cs

using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.Drawing.Imaging;namespace CaptureToImage{ public partial class Snap : System.Web.UI.Page {  protected void Page_Load(object sender, EventArgs e)  {   string url = string.Empty;   url = Request.QueryString[0];   try   {    GetImage thumb = new GetImage(url, 1024, 768, 800, 600);    System.Drawing.Bitmap x = thumb.GetBitmap();    x.Save(Response.OutputStream, ImageFormat.Jpeg);    Response.ContentType = "image/jpeg";   }   catch (Exception ex)   {    Response.Write(ex.Message);   }  } }}

类文件：GetImage.cs

using System;using System.Drawing;using System.Drawing.Imaging;using System.Windows.Forms;using System.Web.UI;namespace CaptureToImage{ public class GetImage {  int S_Height;  int S_Width;  int F_Height;  int F_Width;  string MyURL;  public int ScreenHeight  {   get   {    return S_Height;   }   set   {    S_Height = value;   }  }  public int ScreenWidth  {   get   {    return S_Width;   }   set   {    S_Width = value;   }  }  public int ImageHeight  {   get   {    return F_Height;   }   set   {    F_Height = value;   }  }  public int ImageWidth  {   get   {    return F_Width;   }   set   {    F_Width = value;   }  }  public string WebSite  {   get   {    return MyURL;   }   set   {    MyURL = value;   }  }  public GetImage(string WebSite, int ScreenWidth, int ScreenHeight, int ImageWidth, int ImageHeight)  {   this.WebSite = WebSite;   this.ScreenHeight = ScreenHeight;   this.ScreenWidth = ScreenWidth;   this.ImageHeight = ImageHeight;   this.ImageWidth = ImageWidth;  }  [STAThread]  public Bitmap GetBitmap()  {   WebPageBitmap Shot = new WebPageBitmap(this.WebSite, this.ScreenWidth, this.ScreenHeight);   Shot.GetIt();   Bitmap Pic = Shot.DrawBitmap(this.ImageHeight, this.ImageWidth);   return Pic;  } } public class WebPageBitmap {  WebBrowser MyBrowser;  string URL;  int Height;  int Width;  public WebPageBitmap(string url, int width, int height)  {   this.URL = url;   this.Width = width;   this.Height = height;   MyBrowser = new WebBrowser();   MyBrowser.ScrollBarsEnabled = false;   MyBrowser.Size = new Size(this.Width, this.Height);  }  public void GetIt()  {   NavigateUrl(this.URL);   while (MyBrowser.ReadyState != WebBrowserReadyState.Complete)   {    Application.DoEvents();   }  }  public delegate void DelUserHandler(string url);  public void NavigateUrl(string url)  {   try   {    if (this.MyBrowser.InvokeRequired)    {     DelUserHandler handler = new DelUserHandler(NavigateUrl);     MyBrowser.Invoke(handler, url);    }    else    {     this.MyBrowser.Navigate(url);    }   }   catch (Exception ex)   {    throw new Exception("NavigateUrl()" + ex.Message);   }  }  public Bitmap DrawBitmap(int theight, int twidth)  {   Bitmap myBitmap = new Bitmap(this.Width, this.Height);   Rectangle DrawRect = new Rectangle(0, 0, this.Width, this.Height);   MyBrowser.DrawToBitmap(myBitmap, DrawRect);   System.Drawing.Image imgOutput = myBitmap;   System.Drawing.Bitmap oThumbNail = new Bitmap(twidth, theight, imgOutput.PixelFormat);   Graphics g = Graphics.FromImage(oThumbNail);   g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighSpeed;   g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighSpeed;   g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBilinear;   Rectangle oRectangle = new Rectangle(0, 0, twidth, theight);   g.DrawImage(imgOutput, oRectangle);   try   {    return oThumbNail;   }   catch   {    return null;   }   finally   {    imgOutput.Dispose();    imgOutput = null;    MyBrowser.Dispose();    MyBrowser = null;   }  } }}

PS：项目中需要添加引用System.Windows.Forms

希望本文所述对大家asp.net程序设计有所帮助。

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