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Why is the Url value in C# WebBrowser always null?

I am trying to load a local HTML file into an instance of C# WebBrowser (WinForms).
This is what I am doing:
string url = #"file:///C:MyHtml/hello.html";
myWebbrowser.Url = new Uri(url, UriKind.Absolute);
object test = myWebbrowser.Url; // breakpoint here
The path above is correct; if I copy it and paste into an external browser, the file is immediately opened. But the instance of WebBrowser does not want to react. I set a breakpoint in the last line of the snippet, and what I get there is that myWebbrowser.Url is null (the test variable). The control remains correspondingly empty.
myWebbrowser.AllowNavigation is explicitly set to true. I have also tried all possible versions of slashes and backslashes; the result is always the same. The version of the webbrowser seems to be 11 (myWebbrowser.Version = "{11.0.18362.1139}"). I am working in Windows 10, VS 2019.
What can be wrong in this setup?

The path above is correct; if I copy it and paste into an external browser, the file is immediately opened. But the instance of WebBrowser does not want to react. I set a breakpoint in the last line of the snippet, and what I get there is that myWebbrowser.Url is null.
I was able to replicate this exact issue, it's because the property of the Url doesn't get actually set until the document has actually finished loading.
To resolve this issue, you must handle the DocumentCompleted event. You can do so for example:
string url = #"file:///C:MyHtml/hello.html";
myWebbrowser.DocumentCompleted += MyWebbrowser_DocumentCompleted;
myWebbrowser.Url = new Uri(url, UriKind.Absolute);
Create a new routine to handle the DocumentCompleted event:
private void MyWebbrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
string test = myWebbrowser.Url.ToString();
}
You can also get the Url from the WebBrowserDocumentCompletedEventArgs:
string testUrl = e.Url.ToString();
I am not sure exactly why when setting the Url and then checking it, it is null, I haven't found anything to explain why. My only guess is that it may be an invalid Url and or path, if navigation succeeds then that property is set.
Edit: upon looking at the source for WebBrowserDocumentCompleted, it does seem the Url property is only set in the DocumentCompleted, you can see more there.
Please note: you must register the DocumentCompleted event first before setting the Url property as when you do, it will navigate first and you will not receive the DocumentCompleted event.

I was able to find out why it did not want to function, at least I hope so. The "hello.html" file contained calls to jquery and THREE.js, while WebBroser seems not to support the latter. Therefore I did not see any content in the control. After I threw out THREE.js and inserted most simple HTML code, it worked just OK! Now I am busy trying to bring WebBrowser to support THREE.js (there exists a skeptical opinion about this, though).

C#, No video, audio only, VLC using multiple forms, Black Screen?

Can someone please tell me whey I am getting a black screen with no video, only sound?
private void screen1btnPlay_Click(object sender, EventArgs e)
{
ScreenOne playScreen1 = new ScreenOne();
playScreen1.PlayScreenOne();
}
... and the other form is like this:
public partial class ScreenOne : Form
{
public ScreenOne()
{
InitializeComponent();
}
public void PlayScreenOne()
{
axVLCPlugin21.playlist.add("file:///" + #"Filepath", null);
axVLCPlugin21.playlist.play();
}
}
Sound works fine, but no video. All the properties of the VLC are left to default, is there something I need to change when using this plugin across multiple forms? Anyone know what's wrong?
Update:: I rebuilt the program in WPF and I am having the same problem. When I have a button on the second form (same form as player) it works fine, as soon as I call it from the main form, sound only. ugh!

I dont know but i can give some solution suggestions,
Make sure the VLC program is installed as 32-bit. I dont know, I've solved a problem that way.
I think high probabilty your problem is based on about "C:\Program Files (x86)\VideoLAN\VLC\plugins" Check your plugins. maybe your audio_filter, audio_mixer, audio_output plugins are missing.
you can remove Vlc, then download and install last VLC 32 bit.
I think that will solve your problem. Dont forget AxAXVLC works with vlc plugins.

I figured out my problem on my own!
When I was creating this instance,
ScreenOne playScreen1 = new ScreenOne();
I was actually creating a redundant instance of what I was trying to do, I'm not sure if that's the right way to put it but I basically already had an instance of the second form and was making another separate instance of the form that was named differently.
I already had in my code to open the second form
Screen2 Screen2 = new Screen2();
private void openScreen2Button_Click(object sender, EventArgs e)
{
Screen2.Show();
}
Then later was doing this which is WRONG, I was adding playscreen1 when I should still have been using Screen2.
Screen2 playScreen1 = new Screen2();
playScreen1.PlayScreenOne();
So when I wanted to use the method to play the media player on the second form from the first one, I just needed to use the same instance of Screen2 that I had created to open the form to begin with instead of created a new instance for what method I wanted to use.
IDK if my explanation makes sense, or maybe its basics to most people (I'm a noob), but if anyone comes across this problem, message me and I'll try to help.
o7

Automating Google Maps in C# Web Browser (issue executing javascript properly)

NOT using API
I am currently attempting to use a web browser in C# to load google maps and automatically focus on my current location, however, for some reason I cannot get this to work properly. The idea is simple. Load Google maps, and either execute the script to focus on my current location:
mapBrowser.Document.InvokeScript("mylocation.onButtonClick");
Or, invoke the button click through an HtmlElement:
HtmlElement myLocationButton = mapBrowser.Document.GetElementById("mylocation");
myLocationButton.InvokeMember("click");
But, of course neither of these methods actually work correctly, the coordinates returned are incorrent and the map never actually focuses. Any ideas on how I can fix this issue properly? The scripts aren't invoked until after the document is actually loaded:
private void mapBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
if(mapBrowser.Url.ToString() == "https://www.google.com/maps/preview/")
{
try
{
//HtmlElement myLocationButton = mapBrowser.Document.GetElementById("mylocation");
//myLocationButton.InvokeMember("click");
mapBrowser.Document.InvokeScript("mylocation.onButtonClick");
//mapBrowser.Document.InvokeScript("focus:mylocation.main");
}
catch (Exception ex)
{
MessageBox.Show("Error Invoking Script: " + ex.Message);
}
}
}
so I don't believe that is the cause of my problem. Even more frustratingly, the auto-focus works fine if I click the button manually.
Any help is appreciated, thank you!
(NOTE, you may have to go into IE and allow Google maps access to your location in order to replicate this issue properly)

I've had problem few times that WebBrowser control uses too old version of IE. You need to modify registry to get it to use newer version of IE.
I tried "https://www.google.com/maps/preview/" with both IE 8 and 9 and it gave me an error, but it works on IE 10.
See: http://weblog.west-wind.com/posts/2011/May/21/Web-Browser-Control-Specifying-the-IE-Version

Webbrowser control is not showing Html but shows webpage

I am automating a task using webbrowser control , the site display pages using frames.
My issue is i get to a point , where i can see the webpage loaded properly on the webbrowser control ,but when it gets into the code and i see the html i see nothing.
I have seen other examples here too , but all of those do no return all the browser html.
What i get by using this:
HtmlWindow frame = webBrowser1.Document.Window.Frames[1];
string str = frame.Document.Body.OuterHtml;
Is just :
The main frame tag with attributes like SRC tag etc, is there any way how to handle this?Because as i can see the webpage completely loaded why do i not see the html?AS when i do that on the internet explorer i do see the pages source once loaded why not here?
ADDITIONAL INFO
There are two frames on the page :
i use this to as above:
HtmlWindow frame = webBrowser1.Document.Window.Frames[0];
string str = frame.Document.Body.OuterHtml;
And i get the correct HTMl for the first frame but for the second one i only see:
<FRAMESET frameSpacing=1 border=1 borderColor=#ffffff frameBorder=0 rows=29,*><FRAME title="Edit Search" marginHeight=0 src="http://web2.westlaw.com/result/dctopnavigation.aspx?rs=WLW12.01&ss=CXT&cnt=DOC&fcl=True&cfid=1&method=TNC&service=Search&fn=_top&sskey=CLID_SSSA49266105122&db=AK-CS&fmqv=s&srch=TRUE&origin=Search&vr=2.0&cxt=RL&rlt=CLID_QRYRLT803076105122&query=%22LAND+USE%22&mt=Westlaw&rlti=1&n=1&rp=%2fsearch%2fdefault.wl&rltdb=CLID_DB72585895122&eq=search&scxt=WL&sv=Split" frameBorder=0 name=TopNav marginWidth=0 scrolling=no><FRAME title="Main Document" marginHeight=0 src="http://web2.westlaw.com/result/dccontent.aspx?rs=WLW12.01&ss=CXT&cnt=DOC&fcl=True&cfid=1&method=TNC&service=Search&fn=_top&sskey=CLID_SSSA49266105122&db=AK-CS&fmqv=s&srch=TRUE&origin=Search&vr=2.0&cxt=RL&rlt=CLID_QRYRLT803076105122&query=%22LAND+USE%22&mt=Westlaw&rlti=1&n=1&rp=%2fsearch%2fdefault.wl&rltdb=CLID_DB72585895122&eq=search&scxt=WL&sv=Split" frameBorder=0 borderColor=#ffffff name=content marginWidth=0><NOFRAMES></NOFRAMES></FRAMESET>
UPDATE
The two url of the frames are as follows :
Frame1 whose html i see
http://web2.westlaw.com/nav/NavBar.aspx?RS=WLW12.01&VR=2.0&SV=Split&FN=_top&MT=Westlaw&MST=
Frame2 whose html i do not see:
http://web2.westlaw.com/result/result.aspx?RP=/Search/default.wl&action=Search&CFID=1&DB=AK%2DCS&EQ=search&fmqv=s&Method=TNC&origin=Search&Query=%22LAND+USE%22&RLT=CLID%5FQRYRLT302424536122&RLTDB=CLID%5FDB6558157526122&Service=Search&SRCH=TRUE&SSKey=CLID%5FSSSA648523536122&RS=WLW12.01&VR=2.0&SV=Split&FN=_top&MT=Westlaw&MST=
And the properties of the second frame whose html i do not get are in the picture below:
Thank you

I paid for the solution of the question above and it works 100 %.
What i did was use this function below and it returned me the count to the tag i was seeking which i could not find :S.. Use this to call the function listed below:
FillFrame(webBrowser1.Document.Window.Frames);
private void FillFrame(HtmlWindowCollection hwc)
{
if (hwc == null) return;
foreach (HtmlWindow hw in hwc)
{
HtmlElement getSpanid = hw.Document.GetElementById("mDisplayCiteList_ctl00_mResultCountLabel");
if (getSpanid != null)
{
doccount = getSpanid.InnerText.Replace("Documents", "").Replace("Document", "").Trim();
break;
}
if (hw.Frames.Count > 0) FillFrame(hw.Frames);
}
}
Hope it helps people .
Thank you

For taking html you have to do it that way:
WebClient client = new WebClient();
string html = client.DownloadString(#"http://stackoverflow.com");
That's an example of course, you can change the address.
By the way, you need using System.Net;

This works just fine...gets BODY element with all inner elements:
Somewhere in your Form code:
wb.Url = new Uri("http://stackoverflow.com");
wb.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(wbDocumentCompleted);
And here is wbDocumentCompleted:
void wb1DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
var yourBodyHtml = wb.Document.Body.OuterHtml;
}
wb is System.Windows.Forms.WebBrowser
UPDATE:
The same as for the document, I think that your second frame is not loaded at the time you check for it's content...You can try solutions from this link. You will have to wait for your frames to be loaded in order to see its content.

The most likely reason is that frame index 0 has the same domain name as the main/parent page, while the frame index 1 has a different domain name. Am I correct?
This creates a cross-frame security issue, and the WB control just leaves you high and dry and doesn't tell you what on earth went wrong, and just leaves your objects, properties and data empty (will say "No Variables" in the watch window when you try to expand the object).
The only thing you can access in this situation is pretty much the URL and iFrame properties, but nothing inside the iFrame.
Of course, there are ways to overcome teh cross-frame security issues - but they are not built into the WebBrowser control, and they are external solutions, depending on which WB control you are using (as in, .NET version or pre .NET version).
Let me know if I have correctly identified your problem, and if so, if you would like me to tell you about the solution tailored to your setup & instance of the WB control.
UPDATE: I have noticed that you're doing a .getElementByTagName("HTML")(0).outerHTML to get the HTML, all you need to do is call this on the document object, or the .body object and that should do it. MyDoc.Body.innerHTML should get the the content you want. Also, notice that there are additional iFrames inside these documents, in case that is of relevance. Can you give us the main document URL that has these two URL's in it so we / I can replicate what you're doing here? Also, not sure why you are using DomElement but you should just cast it to the native object it wants to be cast to, either a IHTMLDocument2 or the object you see in the watch window, which I think is IHTMLFrameElement (if i recall correctly, but you will know what i mean once you see it). If you are trying to use an XML object, this could be the reason why you aren't able to get the HTML content, change the object declaration and casting if there is one, and give it a go & let us know :). Now I'm curious too :).

Problem while using WebKit browser's InvokeScriptMethod()

I am using WebKit browser control in my WPF application. I am using it because I want to rendered Protovis enabled HTML on it. Till this point I am successful. Now, I want to pass some parameters specially arrays of double, int and strings to one of the Java script method of the rendered page within the control. I tried InvokeScriptMethod() API from WebKit but it did not work for me if I want to pass parameter(s). Everything works well if I invoke the script method which doesn't take any parameter.
Can somebody help me? I am desperate for it.:)
Thanks,
Omkar

I get HRESULT as E_FAIL if I don't wait until the site is fully loaded.
You have to wait until this event:
private void webKitBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
object[] arr = {"some parameter"};
String returned = webKitBrowser1.Document.InvokeScriptMethod("JavascriptFunctionName", arr) as String;
}
is fired. After that, everything worked fine for me.

You can use,
webKitBrowser1.StringByEvaluatingJavaScriptFromString("javascript:YourMethod();");