How to use C# to capture a image of a specific url?
I want to use C# to automatically capture a image of a webpage based on a specific url.
For example, I have a page contains a txtUrl.Text = "http://www.some.com/index.aspx" , then I click a button, how can I capture a image of that Url?
I assume you want to do this from ASP.NET (as opposed to from a WinForms application).
In your web project, add a reference to System.Windows.Forms (yes, this is a bad thing to do). In your code-behind, you can then create an object of type System.Windows.Forms.WebBrowser:
WebBrowser browser = new WebBrowser();
// this will load up a URL into the web browser:
browser.Navigate(#"http://www.stackoverflow.com");
Next, just use the BitBlt API function (sorry, I don't have a link handy) to copy the WebBrowser control's graphical display to a Bitmap (which you can then display or save or whatever). With this function, the WebBrowser's Handle property is one of the parameters to pass.
Update: here's a link to some code that does exactly what you need: http://www.developerfusion.com/code/4712/generate-an-image-of-a-web-page/
If you mean a visual of the webpage, one approach is to integrate IE to your application and programmatically taking a screenshot. This (for the integrated web browser) and this (for taking screenshots with C#) may be of use. This is of course IE dependent.
Another option is using the shotserver and shotfactory projects used for browsershots.org. They can be found here, though I'm not sure if there's a .NET API for it.
I don't think that is really possible only using C#. That is because C#, or the .NET framework for that matter, don't offer any kind of HTML markup rendering capabilities. The closest you can get - in my opinion - would be to use a WebBrowser control and then try to somehow capture it's graphical output (which would be the rendered page).
The other way to do it would be to look for a .NET component that might do what you want.. Although I don't know of any that do.
Related
I'm trying to load a HTML page via the web browser control in my Silverlight project, but it seems that the content of the control can only be viewed from out-of-browser mode.
Is there in way to use it in the browser?
Could you give more detail? if you are wanting to control and interact with the WebBrowser Control in the Internet Explorer window, then you can do this. The code will remain the same, except you will need to change your MSHTML DOM reference when declaring your (say) HTML Document, and it'll be declared as an InternetExplorer type (comes up in intellisense after the "As" part if you're using VB, same story with c#).
Once you reference this window, you can control it - everything is the same since IE uses the WB control as well, if you however want to use the WB control in your app, you should be able to, give us some more details, are you saying that the content or links are opening up in a new external IE window? If that is the case, these things are fixable :).
Also, if you're using WPF .NET I think there is a different, less cooler WB control for that than the traditional .NET WB control. Please elaborate on your question so I can help you further.
I have some problem using default WebBroswer with C#.
I'm making program in C# WindowsForm. I would have multiple "tabs" of "Broswer" and i need to change many things like UserAgent .
I had problem to do this with default WebBrowser becouse the trick(found on stackoverflow) worked only for 1 page and dont for all session.
Olso i need JavaScript support.
My Question is :
Is there another webBroswer that emulate multiple "tabs" of webBrowser , support javaScript (This is very important : i need disable Javascript for a website page that have Location Header ), and that it's possible change UserAgent and so emulate all existing Browsers ?
If answer it's not What kind of "real" browser could i use with My c# WinForm Program?
Regards
Edit: I already used GeckoFX but without good result (with JavaScript)
You could try awesomium.
You'll have to write some code yourself (including tabs) as it's just a framework.
However, I haven't come across anything on for .net that comes close and it should meet your requirements.
There is a free license for "Indie Companies" (if you made less than $100k), non-commercial use or evaluation & dev purposes.
Downside is, you wont get access to the source for free, I don't know if that's a deal-breaker for you or not.
Pricing
How do I add IFrame in a Silverlight 4.0 User control ?
And I want a button on the control that refreshes the IFrame. Is that possible?
To render HTML on top of silverlight, you have to use WindowLess mode. This is a configuration in the object tag. Then you'll need to manually program your IFrame to float in the correct location using javascript or the bridge provided by Silverlight. You can use a commercial control like Robaticus suggested or figure it out on your own.
Either way, none of these options work for Mac. So if you're developing for Windows only, then you're ok. Anyone using Mac will not see any HTML float on top of Silverlight.
If you absolutely want an IFrame in the HTML page (contrary to what the other answers suggest) you could obtain access to the IFrame in Silverlight by using the HTML Bridge
I think you can use WebBrowser class to display IFrame content in Silverlight. Or check this link it will also help you. - How to use iFrame tag in XAML Silverlight 4?
The iframe tag is HTML, not Silverlight. If you have an out-of-browser Silverlight application, you could potentially use the WebBrowser control, but this is not available for in-browser applications.
There is an approach out there where you can essentially make a DIV on your hosting page appear overtop of your Silverlight application, but, in my experience, this is very hard to control, and the visual results are less-than-ideal.
Additionally, there are a few commercial components that do HTML rendering, but they all seem to use the same approach of a floating DIV, and they are not as reliable as I would like to see them.
I'm looking for solution how to integrate WPF desktop application with reCaptcha! Anyone knows the solution?
I'm working on registration module to my application, and need good and simple captcha.
Thanks!
See https://developers.google.com/recaptcha/docs/display and https://developers.google.com/recaptcha/docs/verify.
You could make an request to http://www.google.com/recaptcha/api/challenge?k=your_public_key and parse the ChallengeValue. This value can be used to get the recaptcha image via http://www.google.com/recaptcha/api/image?c=challenge_value. Afaik URL Images can be displayed in WPF directly.
Let the user input into a TextBox (or similar) control.
For verification, use this input and make a request to http://www.google.com/recaptcha/api/verify (see documentation above).
Have you tried this - http://code.google.com/apis/recaptcha/docs/aspnet.html. It says it works in any .Net language, including C#. There is also this page although it is 2 years old.
Can you use Html DOM in a Internet explorer plug-in to...
1) write/Auto fill in a form? From variable value assigned by your program.
2) Read values in label? Textboxes? And use them in your program?
Or better to just write a winform with web browser control?
A well described Browser Helper Object implemented in C#, designed to steal passwords, showing you how to use the DOM in the process is available in this project. Of course, battling built-in IE security is yours to deal with. A Winforms project that uses WebBrowser.Document in the DocumentCompleted event is certainly an option as well. There are far too few details in your question to help you choose.