ASP.NET screenshot page - c#

Related Stack Overflow question is Programmatically get a screenshot of a page.
My users will be logged into a private system, and I want to have a button on the page that says "Take Screenshot". This will link into the support system, and when they take the screen shot, it creates a new ticket with the screen shot as an automatic attachment.
Content is variable, depending on who you are logged in as! This means I can't use an external screen shotting tool.
Ideally, I would like all the HTML to be rendered to a bitmap which is saved to a disk. Is there some sort of server-side Internet Explorer component that can render the HTML and save it as a BMP?
Kierren made good points. If I can grab the HTML via JavaScript, is there any server-side plugin that can render the HTML as an image as viewed through Internet Explorer?

I did some unsuccesful attempts with that in the past. I could not get the solution which works seemlessly but here are some I have had near-sucess (i.e. for most of the URLs) [Since I was doing POC, results did not matter] See if that helps
WebBrowser.DrawToBitmap() or other methods?
http://www.codeproject.com/KB/graphics/html2image.aspx

I have not heard of an HTML-to-bitmap converter before, but there are definitely HTML-to-PDF options,
http://www.htm2pdf.co.uk/
and
http://html-pdf-converter.com/
to name a couple.

Related

Is it possible to encrypt the source of iframe

I have a webpage which has a iframe, textbox and button but nothing else... user types a URL to the textbox then clicks on the button. after that, URL is assined as the source of the iframe.
what happenes after is a java applet takes the screenshot of the webpage etc. etc.
What I discovered today, in Google Chrome, there is this option in the right click menu named "inspect element". With the help of this feature, user are likely to change whats inside of an iframe and manipulates the original data. Does anyone know how can I encrypt the source of iframe.
P.S. source of iframe is authenticated data.
This is what it look like before manupilation
This is after manupilation
The short answer to your question is "no". Html is a client-side SCRIPT language; while you may find ways to make things increasingly difficult to "manipulate", you ultimately have no ability to entirely prevent a user from seeing every single detail of what you are trying to do with 1 significant exception and that is the use of an applet or plugin (ie: flash, java, activex).
To help with your problem, if you are already using an applet, why not leverage that over using an iframe? You could also consider using the applet to generate a jpeg for delivery rather than HTML.

how to download the image which will be displayed after a cache image on the web page?

I want to download an image from a cartoon website. and my app is WinForm,not WebForm.
So let's say that there is an image on the a.html.
Normally, when I click the previous page and am redirected to this page,
there will be a image :"image is loading",let's say A.jpg, in the same block.
After 5 seconds, the real one,let's say B.jpg, will be displayed.
So what I got is only the caching image rather than the one,B.jpg, which I want.
So..... how should I do it?
Thanks in advance.
ps: I have posted this qustion for more than 48 hours, and only got a few of answers which don't solve my problem.
I am wondering that why there are only 2 people posted their answers?
Is my question not clear?
If any, please let me know.
Thanks
EDIT: Original answer removed since I misunderstood the question entirely.
What you want to do is basically HTML scraping: using the actual html of the page to discover where files are hosted and download them. Because I'm not sure if there are any legal reasons that would prevent you from downloading the image files in this manner, I'm just going to outline an approach to doing this and not provide any working samples or anything. In other words, use this information at your own risk.
Using fiddler2 in Firefox, you should be able to find the domain and full url that one of the images is downloaded from. Basically just start fiddler2, navigate to the site in firefox, and then look for the biggest file that is downloaded. That will tell you exactly where the image is coming from.
Next, take a look at the HTML source code for the page you are viewing. The way this particular site works, it looks like it hides the previous/next downloads in a swf or something, but you can find the urls in the javascript for the page. Look for a javascript array called picArr.
To download these using a WinForms app, I would use the WebRequest object. Create a request for each image url and save the response to disk.

Browser Print Generation

I use:
window.print();
to print documents.
Problem:
As you guys know that browsers automatically adds page's title, path on top of the print page and page number and date on footer of the page.
But the client has asked me to remove all those things from the page or change their color to white so that they are not visible.
Question:
Is it possible to remove those things from page generated by the browser?
(I suspect answer might be no but no sure; possibly this can be controlled :))
This is a setting on the browser and can be turned on and off.
http://www.mintprintables.com/print-tips/header-footer.php
Only way to do this is via ActiveX for IE.
If you can do something server side, you could create a PDF file which the user can then print. I've not seen how to this on the browser itself, although I'd be interested to see if anyone else has.

C# code for saving an entire web page? (with images/formatting)

I've been struggling to find an exmample of some C# code (I'm using C# Visual Studio 2008 Express) that can programmatically save an entire web page (given a URL) including the images and formatting (e.g. CSS). The intention is that in a subsequent phase I'd ship this off (not sure how yet) so it could be viewed later via a browser.
Is there an example of the most simple approach (leveraging the .NET Framework methods) to save an entire web page? Saving as one page with a subdirectory for images, or otherwise. Basically the same as what you get with browsers when you say "save entire web page".
The simplest way is probably to add a WebBrowser Control to your application and point it at the page you want to save using the Navigate() method.
Then, when the document has loaded, call the ShowSaveAsDialog method. The user can then save the page as a single file, or a file with images in a subdirectory.
[Update]
Having now noticed "programatically" in your question, the above approach is not ideal as it requires either user involvement or delving into the Windows API to send input using SendKeys or similar.
There is nothing built-in to the .NET Framework that does all of what you ask.
So my approach revised would be:
Use System.NET.HttpWebRequest to get the main HTML document as a string or stream (easy).
Load this into a HTMLAgilityPack document where you can now easily query the document to get lists of all image elements, stylesheet links, etc.
Then make a separate web request for each of these files and save them to a subdirectory.
Finally update all relevent links in the main page to point to the items in the subdirectory.
In effect you would be implementing a very simple web browser. You may run into issues with pages that use JavaScript to dynamically alter or request page content, but for most pages this should give acceptable results.
From code Project: ZetaWebSpider
It's definitely not elegant, but you could navigate a System.Windows.Forms.WebBrowser to the URL and then call its ShowSaveAsDiagog() method to save the page.

Read & display text file in javascript

The user needs to click on browse button to browse his system .He then selects a text file & clicks ok.Once he clicks ok all the data in the text file should be displayed in a text area.How do I do that? I am using JavaScript & c# designing aspx pages.It would be preferable if i avoid round trip to the server.
You can't do it without a trip to the server, the only way for you to get the content of the file is by submitting it as part of a form. You can make the trip to the server happen in an iframe via XHR and then update the text area with the result from the XHR call, so it sort of seems like one wasn't involved, but you can't directly access the content of files of the user's machine, for obvious reasons.
I know you said you would prefer a round trip, but its the only way you are going to be able to accomplish what you want.
You could put the file upload in an iframe, and do the upload behind the scenes (No page refresh, gmail does this :) ) then use AJAX to download the data and insert it into the textarea.
It can't in general be done, as answers here outline.
However, it can be done in Firefox 3+ only, using the uploadfield.files array. Other browsers would have to fall back to the server round-trip.
For security reasons, JavaScript cannot access the local filesystem like that.
Javascript cannot do that without putting a severe security risk on the user. That said, the file will need to be posted to your server.
As other posters here have indicated, you're not allowed to access the local filesystem from Javascript directly. But you can set up an action on your server to take the file form POST input, and simply echo the data right back out to the response. If you hide an iframe inside your page as the form POST target, that response data can appear in the hidden iframe, and then the page won't have to reload. Then once the iframe has loaded with the text, you can use JS to pull the text out of the iframe, and put it into the text area that you're interested in.
Alternately, if you're inclined to restrict usage to Firefox users with an extension, you should be able to accomplish this without a roundtrip using a Greasemonkey user script (see www.greasespot.com) or something like it, that uses the custom Mozilla extensions.

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