使用C＃使用默认浏览器发送HTTP Post

Question

I am wondering if it is possible to send POST data with the default browser of a computer in C#.

Here is the situation. My client would like the ability to have their C# application open their browser and send client information to a webform. This webform would be behind a login screen. The assumption from the application side is that once the client data is sent to the login screen, the login screen would pass that information onto the webform to prepopulate it. This would be done over HTTPS and the client would like this to be done with a POST and not a GET as client information would be sent as plain text.

I have found some wonderful solutions that do POSTS and handle the requests. As an example http://geekswithblogs.net/rakker/archive/2006/04/21/76044.aspx

So the TL;DR version of this would be

1) Open Browser

2) Open some URL with POST data

Thanks for your help,

Paul

Answer 1

I've handled a similar situation once by generating an HTML page on the fly with a form setup with hidden values for everything. There was a bit of Javascript on the page so that when it loaded, it would submit the form, therefore posting the data as necessary.

I suspect this method would work for you.

1. Generate a dictionary of fields and values
2. Generate an HTML page with the Javascript to automatically submit when page is loaded
3. Write page to a temp location on disk
4. Launch default browser with that page

Remember though that POST data is sent plaintext as well. POST is generally the way to go for more than a couple fields, as you can fit in more data (2048 byte limit on URLs) and that your user has a friendly URL to see in their browser.

Answer 2

Nothing is sent as plain text when you use SSL, it is encrypted. Unless you set what the default browser is (IE, Firefox, Chrome, etc), then you'll have to figure out what the default browser is and use its API to do this work (if it's possible).

What would probably be must faster and more efficient would be to open the default browser by invoking a URL with Start Process and pass the information on the query string (this is doing a GET instead of a POST, which I know isn't what you're asking for).

The response from the server could be a redirect, and the redirect could send down the filled-out form (storing the values in session or something similar).

That way the complexity is pushed to the website and not the windows application, which should be easier to update if something goes wrong.

HTH

Answer 3

Can you compile your logic in C# and then call it from PowerShell? From PowerShell you can very easily automate Internet Explorer . This is IE only but you might be able to also use WaitnN .

Answer 4

Anything you put at the end of the URL counts as the querystring, which is what GET fills. It is more visible than the POSTed data in the body, but no more secure with regard to a sniffer.

So, in short, no.