C# Webbrowser navigating links in order - c#

I'm trying to teach myself C# and to start I'm trying to convert a program I originally wrote in Autoit.
I'm using a Windows Application Form and the program is suppose to take one or two links as input. Navigate to those to pages, grab some links from a table, then visit each of those pages to grab some content.
If only one link is entered it seems to go to that page and grab the links from a table like it is suppose to. If two links are entered it seems to only grab the links from the second table.
So if two links are passed this method
private void getPageURLList(string site1, string site2)
{
getPageURLList(site1);
getPageURLList(site2);
}
Calls the same method that gets called when there is only one link
private void getPageURLList(string site)
{
webBrowser.DocumentCompleted += createList;
webBrowser.Navigate(site);
}
I'm pretty sure the issue is "Navigate" is getting called a second time before createList even starts the first time.
The reason I am using WebBrowser is because these pages use Javascript to sort the links in the table so HTTPRequests and the HTMLAgilityPack don't seem to be able to grab those links.
So I guess my question is: How can I keep my WebBrowser from navigating to a new page until after I finish what I'm doing on the current page?

You have to make a bool variable to know when the first proccess has completed. And then start the other. Application.DoEvents() will help you.
Note that all this events run in the main thread.

In your documentcompleted event you do your link processing. At the end of the link processingyou tel the browser to navigate to the next url

Related

Stop multiple WebBrowsers from starting yt-videos?

I'm working with a winform TabControl showing WebBrowsercontrols to display youtube videos.
However with two videos or more it becomes really annoying as all videos start directly.
I basically need to find out if there is a JS function, html code or a simple WebBrowser property to change, so videos are paused.
It might come in handy to find something like that for video quality too.
Has anybody ever heard of/seen where this option is stored? Or maybe the Js function itself being invoked when manually setting the quality?
EDIT:
b.DocumentCompleted += delegate { b.DocumentText=b.DocumentText.Insert(b.DocumentText.IndexOf("class=\"video-stream html5-main-video\""), "autoplay=false ");};
b.Url = new System.Uri(inp[s], System.UriKind.Absolute);
Basically this should add a new Event handler on each webbrowser form that modifies the DocumentText when the Uri that is called during creation has loaded.
Even though the browser debugger shows
<video tabindex="-1" class="video-stream html5-main-video" controlslist="nodownload" style=... src=...></video>
this isn't in the actual source code.
However I found
$oa=function(a){g.S(a.o,"video-stream");g.S(a.o,"html5-main-video");var b=a.app.g;b.zc&&a.o.setAttribute("data-no-fullscreen",!0);b.Oh&&(a.o.setAttribute("webkit-playsinline",""),a.o.setAttribute("playsinline",""));b.Nr&&a.o&&a.P(a.o,"click",a.o.play,a.o)};
in the base.js. Is it possible that youtube generates the html from the js?
How can I modify the video-tag attributes then?
I tried to modify when the event handler manipulates the video tag, since there may be DocumentCompleted events thrown from scripts or anything.
delegate (object sender, System.Windows.Forms.WebBrowserDocumentCompletedEventArgs e){
if (e.Url.AbsolutePath != ((System.Windows.Forms.WebBrowser)sender).Url.AbsolutePath){
//...
However it still fails as there is no occurance of the specific class that on the video tag.
I now dodged this by loading the Url only when the browser tab is selected, if someone finds a real solution, feel free to share

How to resume the app with another page then the suspended?

I need to ask for a passcode every time the app was suspended (and resumed), so I have to show a corresponding page, and after the user enters the pin proceed the app resuming to the page which was shown before suspending. How can I get the page to which I have to proceed? The App.Resume event provides 2 parameters, but both of them are objects. To which type I need to cast these objects to get the proper page's type? Can I get from these parameters the proper page type at all?
I mean
private void OnResuming(object sender, object e)
{
//get the suspended page's type here
}
Thanks :)
I recommend the following:
In OnResuming simply Navigate to the passcode page, but remember the current page before.
OnResuming should look like this:
//...
// the following line returns something like e.g. "MainPage"
var pageTypeName = ((Frame)Window.Current.Content).SourcePageType.Name;
// store pageTypeName in app scope
// Navigate to passcode page ...
When passcode was entered correctly navigate to the previous page.
Second Option:
You can also try to navigate to the passcode page during "OnSuspending". The user will see the passcode page after a resume. After entering the code you can redirect the user to the previous page. Of course you also have to store the type of the current page during OnSuspending accordingly.
The code shown works fine if you have an "easy" interface without e.g. a SplitView. You probably have to tweak it a little if you are working with nested Frames etc.

Get "real" HTML source from website

So, I've come across an issue where my favorite radio station plays a song I don't know while I'm driving. They don't have one of those pages that shows a list of songs that they've played; however, they do have a "Now Playing" section on their site that shows what's currently playing and by who. So, I am trying to write a small program that will poll the site ever 2 minutes to retrieve the name of the song and the artist. Using Chrome dev tools, I can see the song title and artist in the source. But when I view the page source, it doesn't show up. They are using a javascript to run display that info. I've tried the following:
private void button1_Click(object sender, EventArgs e)
{
webBrowser1.Navigate(#"http://www.thebuzz.com/main.html");
webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser1_DocumentCompleted);
}
private void webBrowser1_DocumentCompleted(object sender,
WebBrowserDocumentCompletedEventArgs e)
{
do
{
// Do nothing while we wait for the page to load
}
while (webBrowser1.ReadyState == WebBrowserReadyState.Loading);
var test = webBrowser1.DocumentText;
textBox1.Text = test.ToString();
}
Essentially, I'm loading it into a WebBrowser and trying to get the source this way. But I'm still not getting the part after the javascript is run. Is there a way to actually retrieve the rendered HTML after the fact?
EDIT
Also, is there a way in the WebBrowser to allow scripts to run? I get popups asking me if I want to allow them to run. I don't want to suppress them, I need them to run.
As Jay Tomten said in the comments, you're trying to fix the result of your problem, not the cause. The cause of the problem is that they're using Javascript to update that part of the page. Instead of working around that by letting the Javascript do its update and then reading what it wrote, ask yourself where the Javascript is getting the info from and whether you can go to the same place. Open up something that lets you see web traffic - Fiddler, or Chrome's dev console, for example. Watch for POST calls. One of them will likely be an AJAX request in which the Javascript on the page is getting the current song. Note the URL, inspect the call to see what parameters it sends and what data it gets back. You can use Postman or something like it to assemble a POST request and work out how the Javascript on that site is getting its data, and then write a little code to make your own call to that URL and parse what comes back.

WebBroswer_DocumentCompleted event is not working

I have a form with a browser control. (this control uses IE9 because I set values on registry editor)
This web browser navigates to a specific URL and fills all fields on HTML page and submit them, then result page is displayed.
My problem is that i just want to know when this reslut page is fully loaded or completed so that i can fetch some information.
I use WebBroswer_DocumentCompleted event which works fine for the first page but not for the result page as it triggers before result
page is loaded.
I tried other solution which is to check the div tag inside the result page (this tag only appears when result page is loaded completely) and it works but not always.
My code:
private void WebBroswer_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
HtmlElementCollection elc3 = this.BotBrowser.Document.GetElementsByTagName("div");
foreach (HtmlElement el in elc3)
{
if (el.GetAttribute("id").Equals("Summary_Views")) //this determine i am at the result page
{
// fetch the result
}
}}
That div id is "Summary_Views".
I can provide you the link of that website on demand which is just for BLAST tools and database website for research purpose.
Frames and IFrames will cause this event to fire multiple times. Check out this answer:
HTML - How do I know when all frames are loaded?
Or this answer:
How to use WebBrowser control DocumentCompleted event in C#?
Or ms's kb article:
http://support.microsoft.com/kb/180366
Do you know if there are frames? If so then please say so, so people can help with that. If not then say so, so people can offer alternatives.
My guess is that the content is being generated by JavaScript. If it is then the document is complete before the JavaScript executes and you need to somehow wait until the JavaScript is done. The solution depends upon the web page. So you might need to process multiple document completes for diagnostic purposes and attempt to determine if there is a way to know which one you need.
At last i have solved my problem. I put a timer control from toolbox and set its time interval to 200ms and its Autoreset property to false. I set a tick event which has a code to check every 200ms whether this Div has been loaded or not, after that, Autoreset property is set to true.This solution is working perfectly :)

Opening a browser and filling in some data

i want to know how i can open a browser to a specific web page and then fill out some of the content of the boxes on that page.
My idea is for someone to be able to order a particular item from our internal ordering system. The barcodes for these items are what will populate the fields on the page i want to open.
I no i can open a new instance of ie using Process.Start("IEXPLORE.EXE", url); howver how do i get a handle on that exact ie instance window so i can begin to add the required data to the fields?
Is this even possible?
Thanks very much
WatiN should help with this. I've generally used it for acceptance testing of web apps, but the principle is the same. Open a browser instance, reference stuff in the DOM, manipulate form elements, etc.
In addition to WatiN (as was suggested in another answer), you might consider a load testing package like Web Performance Load Tester. They have a free version that lets you run up to 10 virtual users at a time, which will perform scripted actions.
Another option would be to use a standard WebBrowser object to load your website. The WebBrowser object allows you to access and alter certain web parts. Below is sample code that automatically searches Bing:
private void LoadPage()
{
WebBrowser webBrowser1 = new WebBrowser();
webBrowser1.Navigate("http://www.bing.com");
//Wait for document to load...
while (webBrowser1.ReadyState != WebBrowserReadyState.Complete)
{
Application.DoEvents();
}
//Set the text of the search input
HtmlElement txtTextField = webBrowser1.Document.GetElementById("sb_form_q");
txtTextField.InnerText = "My test text";
//Perform a click on the search button
HtmlElement btnSubmit = webBrowser1.Document.GetElementById("sb_form_go");
btnSubmit.InvokeMember("click");
}

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