這篇文章主要介紹了ASP.NET實現根據URL生成網頁縮略圖的方法,結合實例較為詳細的分析了asp.net生成網頁縮略圖的詳細實現技巧與相關注意事項,需要的朋友可以參考下
本文實例講述了ASP.NET實現根據URL生成網頁縮略圖的方法。分享給大家供大家參考,具體如下:
工作中需要用到根據URL生成網頁縮略圖功能,提前做好準備。
在網上找了份源碼,但是有錯誤:當前線程不在單線程單元中,因此無法實例化 ActiveX 控件“8856f961-340a-11d0-a9”,解決后運行良好,記錄在此備用!
起始頁: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="生成網頁縮略圖"/>
- </div>
- </form>
- </body>
- </html>
調用頁: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>無標題頁</title>
- </head>
- <body>
- <form id="form1" runat="server">
- <div>
- </div>
- </form>
- </body>
- </html>
PS:紅色字體部分是為解決錯誤增加的代碼,強制程序在單線程環境下運行!
調用頁: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);
- }
- }
- }
- }
類文件: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:項目中需要添加引用System.Windows.Forms
希望本文所述對大家asp.net程序設計有所幫助。
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