How to take snapshot from HTML in C# - C# Sample Code(5)

If you are a C# developer, you may want to take snapshot from HTML, and then save as an image file or directly output to client's browser. To add this feature in your c# project, ACA WebThumb ActiveX is your best choice. ACA WebThumb ActiveX is a developer SDK that based ActiveX technology. With a few function calls in your C# project, it takes the snapshot from HTML page and then save as JPG, GIF, PNG, BMP, TIFF, WMF and EMF image. In this tutorial we will see how we can take snapshot from HTML in C# script codes.

Guidelines: Take snapshot from HTML in C#

1. Download ACA WebThumb ActiveX, and then install it.
2. Click Start menu, and then select "Program -> ACASystems -> ACA WebThumb ActiveX Control -> Samples", You will find a C# demo project in the folder c#.
3. You can open this C# demo project with VS2003, VS2005 or VS2008, build and run it.

C# Sampe Code: Take snapshot from HTML

This C-sharp sample script shows how to take screenshot from http://en.wikipedia.org/wiki/Snapshot and then saves as a PNG image file.

// C# - Take screenshot from HTML page

// Specify the image filename.
// [IMPORTANT NOTE]: 
// This sample saves the screenshot image to the folder on the work dir of this script. 
// Please make sure the script has the WRITE permission in this folder.
// You can also set the value to other folder by yourself, for example: 
//   string t_strImageFolder = "c:/tmp";
string t_strImageFolder = Server.MapPath("./");           
string t_strFullImageFile = t_strImageFolder + "\\" + "snapshot-fullsize.png";
string t_strSmallImageFile = t_strImageFolder + "\\" + "snapshot-thumbnail.png";

// Create ActiveX object
ThumbMakerClass t_xSnapshot = new ACAWebThumbLib.ThumbMakerClass();

// Start capture web page from http://en.wikipedia.org/wiki/Snapshot
t_xSnapshot.SetURL("http://en.wikipedia.org/wiki/Snapshot");
t_xSnapshot.StartSnap();

// Save the screenshot to file, image size: full size
t_xSnapshot.SaveImage(t_strFullImageFile);

// Save the screenshot to file, image size: 320x240
t_xSnapshot.SetThumbSize(320, 240, 0);
t_xSnapshot.SaveImage(t_strSmallImageFile);

// Show the image
pictureBox_small.Image = Image.FromFile(t_strSmallImageFile);
pictureBox_full.Image = Image.FromFile(t_strFullImageFile);

C# Sampe Code: Take snapshot from part of HTML in C#

The above sample shows how to take snapshot from fullsize HTML page in your C# project. You can also use ACA WebThumb ActiveX to take snapshot from part of HTML page. To add this feature, you should call GetThumbWidth() and GetThumbHeight() to get the size of whole page, and then call SetClipRect() to set the clip rectangle to the image. This sample script shows how to take a snapshot of a long HTML and break it up into multiple images.

// C# - Take screenshot from part of HTML page

// Specify the image filename.
// [IMPORTANT NOTE]: 
// This sample saves the screenshot image to the folder on the work dir of this script. 
// Please make sure the script has the WRITE permission in this folder.
// You can also set the value to other folder by yourself, for example: 
//   string t_strImageFolder = "c:/tmp";
string t_strImageFolder = Server.MapPath("./");           
string t_strSnapshotPart1 = t_strImageFolder + "\\" + "snapshot-part1.png";
string t_strSnapshotPart2 = t_strImageFolder + "\\" + "snapshot-part2.png";

// Create ActiveX object
ThumbMakerClass t_xSnapshot = new ACAWebThumbLib.ThumbMakerClass();

// Start capture web page from http://en.wikipedia.org/wiki/Snapshot
t_xSnapshot.SetURL("http://en.wikipedia.org/wiki/Snapshot");
t_xSnapshot.StartSnap();

// Get the full size of image
long t_lWholeWidth = t_xSnapshot.GetThumbWidth();
long t_lWholeHeight = t_xSnapshot.GetThumbHeight();
long t_lPartHeight = t_lWholeHeight / 2;

// Save the part 1 of the screenshot to image
t_xSnapshot.SetClipRect(0, 0, t_lWholeWidth, t_lPartHeight);
t_xSnapshot.SaveImage(t_strSnapshotPart1);

// Save the part 2 of the screenshot to image
t_xSnapshot.SetClipRect(0, t_lPartHeight, t_lWholeWidth, t_lPartHeight);
t_xSnapshot.SaveImage(t_strSnapshotPart2);

Other resource about taking sceenshot of web page in C#:

• C# Sample Code (1): How to convert HTML to image in C# (C-sharp)?
• C# Sample Code (2): How to capture web page to image with C# (C-sharp)?
• C# Sample Code (3): How to generate image from HTML with C# (C-Sharp)?
• C# Sample Code (4): How to take screenshot of web page in C# (C-sharp)?
• ASP Sample Code: How to convert HTML to image with ASP?
• Java Sample Code: How to convert HTML to image in Java?
• PHP Sample Code(1): How to convert HTML to image with PHP?
• PHP Sample Code(2): How to convert webpage to image with PHP?
• .Net Sample Code: How to convert HTML to image in ASP.Net??
• FAQ: Which image format is best?
• FAQ: What programming languages does ACA WebThumb ActiveX Control support?
• ACA WebThumb ActiveX Interface Reference
• Free Download ACA WebThumb ActiveX Control
• Wikipedia.org: C Sharp(C#)
• Microsoft MSDN: Visual C# Developer Center