I am trying to login a website by POST method through HttpWebRequest. In the beginning, i create a portrait page to let user to enter username and password and access the web page. I successfully to Post the data and get the HTML content from the website. Finally I using the Webrowser.NavigateTostring method to display the website in the webBrowser I create.
Problem 1: Inside the webBrowser, I can not do any action in the website. In the normal webBrowser, after successfully login I can do any action such as go to event forum..but what i face is I can't navigate to event forum or any forum.
Problem 2: Inside the webBrowser, the image will not showing eg, user picture, product picture. I also trying to use IsolatedStorage method to show the HTML content but it also non work.
What I confusing is wheather the Webrowser.NavigateTostring method is a way to asynchronous operation to the website in internet? and what I doing wrong? or I looking for wrong direction?
Any help would be appreciated. Thank you.
Unfortunately, Set-Cookie is one of the HTTP headers that are not supported.
This way will suffer from these problems as if you load the HTML using WebBrowser.NavigateToString or from Isolated Storage none of the relative links to images, scripts or CSS will work. Also it is impossible to pass any Cookies from HttpWebRequest to the WebBrowser
The way to do this is to use the WebBrowser control itself to do the POST. There is a overload of the WebBrowser.Navigate method as documented on MSDN here. That will allow you to POST data to your URL.
// generate your form data based on the data you got from your "portrait page"
// and get the bytes from that.
// (e.g. write your post data to a MemoryStream as UTF8 and get its bytes)
byte[] formBytes = ...
// write HTTP headers here, including the type of data you're posting, e.g.:
string headers = "Content-Type: application/x-www-form-urlencoded"
+ Environment.NewLine;
Uri uri = ... // where you want the POST data to be sent
this.webBrowser.Navigate(uri, formBytes, headers);
That way your web browser will be properly initialized and your cookies, images, scripts and CSS should all work.
Related
Problem
I have some pages that need dynamic data from website to generate output to users.
A simple solution is an aspx(php, ...) page to generate data and create another html page serving as GUI retrieving data from first page and showing it to users. in this method I can call my GUI page for example form1.aspx and my data page form1.json.aspx.
although I personally like this method, it is not suitable when creating components for it.
Another method that currently I'm using is using same GUI page call itself with a querystring to retrieve data. this page should check for that query string and if it exists, only generate data and remove everything else from page. As an example for this method if I call my page form1.aspx, to retrieve data, I need to call it like form1.aspx?JSON
Here is an example of what I'm doing:
protected void Page_Load(object sender, EventArgs e) {
if (Request.QueryString.ToString().IndexOf("JSON") == 0){
this.Controls.Clear();
Response.Clear();
// send pure data to client
} else {
// render page as GUI
}
}
However this method becomes too messy if I add master page and/or inherit my page from some template page. Master pages can only removed in Page_PreInit and that adds another extra method.
Security controls cause another problem, if user leaves page open for long time until session expires any attempt to retrieve data will fail cause security module will redirect the request to login page.
Next problem is I cannot consolidate my component in package because it needs modification in page (removing master page, clearing page components ...).
What I'm looking for:
1- I'm looking for a solution that I can call my page and get pure data (JSON or XML format) and doing so run a server side method that generates data, so I don't have to worry about what another designer puts in their master page or template.
2- I think it is possible to use axd extension to do this but I don't have a clue about it and couldn't find a helping document either.
3- Is there any better way of doing this. any suggestion or solution to improve this much appreciated.
Page methods. Check this article: http://weblogs.asp.net/craigshoemaker/archive/2008/09/29/using-jquery-to-call-asp-net-ajax-page-methods.aspx or http://encosia.com/using-jquery-to-directly-call-aspnet-ajax-page-methods/
WCF JSON service: http://www.codeproject.com/Articles/327420/WCF-REST-Service-with-JSON
Other ways of doing is using an HTTP Handler. Implement IHttpHandler interface and register your implementation in your Web.config file. Later call it using jQuery ($.get / $.post):
http://msdn.microsoft.com/en-us/library/46c5ddfy.aspx
EDIT
As OP pointed out, in order to access session state in a page method you should use WebMethodAttribute this way:
[WebMethod(EnableSession = true)]
I think you can use webservice instead of aspx page to return a JSON or XML string and then the caller page (any aspx page) will response after process is success.
So with this webservice, any third party page will have access to your server side method.
To create a webservice pls Check this link: Create and use Asp.net web service basic
Regards
i have a little asp.net web application.
it is a front end to a sql-server-2008 database.
after they fill out all the data, they will press submit and the data will be sent to the database.
after this point if the user refreshes the page, the data is posted again!!! how do i disable this from happening?
Send a Location header back to the user that redirects the browser to another page: refresh will then reload that other page rather than resubmit the old form.
This is caused by the last request being a POST request to the page, what do you need to do is a redirect so the last request becomes a GET.
After you have handled the post data you can just do a redirect to the same page with:
Response.Redirect("~/ThePage.aspx");
This will prevent you from presenting a message to the user straight from the code behind, if you want to present a success message using this method you will need to add a querystring or something similar:
Response.Redirect("~/ThePage.aspx?result=success");
And then check on the page bind if the querystring to present a success message is set, such a check could look something like this:
if (Request.QueryString["result"] != null && Request.QueryString["result"].ToString().ToLower() == "success")
{
//Show success message
}
Another solution which probably is superior but might require some more work is to wrap the form in a updatepanel, you can read more about it here: http://ajax.net-tutorials.com/controls/updatepanel-control/
An updatepanel will make the form submit with AJAX instead of full postback.
You need to follow the Post/Redirect/Get pattern which is explained on WikiPedia and alluded to by Femi. In your code after you've done your processing do a Response.Redirect to the desired page.
See this article about the PRG pattern: http://en.wikipedia.org/wiki/Post/Redirect/Get
In short, after the user POSTs (submits) data to your server, you issue a Response.Redirect to have the users browser GET a page. This way, if the user presses the reload button, it is the GET request that is repeated.
I need help with connecting to a certain website via my username & password.
With WebClient I can fill the username field and the password field, but how do I invoke the click method of the button?
And How can I fill a specific textBox that doesn't have an ID?
I tried doing this with webBrowser, but every time I navigate I have to use a new function every time, which makes the work much harder.
Thanks.
What you're trying to do is wrong. If you want to Post some data to a web address (a URL), simply create a web form (a simple HTML form), fill it, and then send it. Just consider these notes:
Your HTML's form action should be the exact URL of the form you're imitating.
Your input controls should have the same name attribute value.
For more information, see Form Spoofing
Look at the web browser control and see if you can use that inside your windows form to perform the task that you are doing. Once you are satisfied with the results, you can make the web browser control invisible, and it'll work just like you do with web response and request calls.
View the source code and find the id of the button (say "Login").
Then use:
HtmlElement elem = webBrowser1.Document.GetElementById("Login");
if (elem != null)
elem.InvokeMember("click");
I have an aspx web page (opener) which opens a popup window
In the popup window I need to retrieve the value of a hidden field which exists in the opener page.
So this is all straight forward using Javascript.
However, here’s the problem, I need the value of the hidden field to be processed SERVER side before the pop up page loads
(Basically, the hidden field contains XML which need to be deserialized server side and the data used to construct the DOM of the popup page)
So how do I pass the data in the hidden field of the opener, to get processed serverside in popup?
The data is Waaay too long to be passed as a GET. i.e. in the querystring of the popup page
What are the other options here?
Retrieve it using Javascript in popup, then do a postback to reload the page (very ugly)
Somehow post the data when opening the popup? Is this possible and can I stil pass other info via the querystring
Any other ideas?
Have a form like this
<form method="POST" action="action.php" onsubmit="open_popup(this);">
<input name="really-big-field" type="hidden">
</form>
also, javascript like this
function open_popup(form)
{
window.open('action.php', 'actionpopup','width=400,height=300');
form.target = 'actionpopup';
}
window.open() will open a popup like you want.
Setting the form's target to the opened popup will make sure that the form will POST to that popup.
Since a POST is made, you can send larger data than you can send using GET.
You can process the data server side in action.php (or in ASP.Net/VB file).
My usual solution to this sort of issue is to use XmlHTTPRequest to post the XML to the server, which simply stores the XML against some unique ID such as a GUID and have the ID returned from the server.
The URL you provide for your popup would then only need to carry this ID rather than the whole XML. Now when the server code on the other end of that URL needs the XML it can use the ID to look up the XML (probably deleting it from its temporary store at the same time) and can process the XML as if had been posted in the request.
Edit: Sorry, I realize this doesn't answer your question. I didn't read it clearly enough and didn't realize you needed to do it server side. I suppose if you wanted to take this path, though, you could then AJAX up your page to build it.
Parent page:
foo = 'bar';
child = open ("popup.html");
// you can now access the new windows functions with child.varname and child.function()
Child page:
alert(window.opener.foo);
Should alert Foo. Therefore you can:
somevar = window.opener.document.getElementById('id').value;
to get the field's value.
I have a javascript code which builds a link with 2 params.
Now, I know how to post these params using the address, but I don't want to use it.
I've tried using cookies for posting the params, but somehow I can't read them on the server side.
this is the client side code
document.cookie="name="+"value";
this is the server side reading code
string s = Response.Cookies[cookieName].Value;
Can you hep me out?
Create a mini form (not an asp.NET web form, just a simple one) with two input type hidden fields named as your parameters. After that create a link or button an tie the onclick event of it to a javascript function (example: onclick="javascript:postIt();").
Then when user clicks the button or the link the function will replace the value of those parameter something like:
document.miniform.parameter1.value = yourvalue1;
document.miniform.parameter1.value = yourvalue2;
document.miniform.submit();
To get the parameters back into code use Request.form("parameter1") and so on...
You can use an Ajax Request to post your data to an ASP.NET form.
To post data to any page, you HAVE TO use the path to that page. As for your problem with setting the cookies, they can only be used by a page in the same domain.
Are you doing an HTTP Post? You could post these values inside a form field. I'd use a hidden input field. You can add one in your markup or add one via the javascript.
Your other option is to use some sort of Ajax and pass JSON or XML in the body of the post.
Cookies are meant to save data client side accross pages and/or sessions.