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Click button after webBrowser1_DocumentCompleted event

I have a C# 4.0 WinForms application, which has a WebBrowser control and 2-buttons.
Clicking the first button sends a URL to the browser to navigate to a specified webSite.
Clicking the second button parses the OuterHtml of the webBrowser1.Document, looking for an "https://..." link for File Download.
The code then uses a webClient.DownloadFileAsync to pull down a file for further use in the application.
The above code successfully works, if I manually click those buttons.
In an effort to automate this for the end-user, I place the first button's click event, i.e. btnDisplayWeb.PerformClick(); in the form's Form1_Load event. This also works, allowing the webBrowser1 to populate its Document with the desired webSite.
However, I am unable to programatically click the 2nd button to acquire the web link for file download.
I have tried to place the 2nd buttons click event within the browser's DocumentCompleted event, as shown below.
private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
btnMyUrl.PerformClick();
}
However, from what I've read on StackOverFlow and other sites, it's possible that this particular event gets called more than once, and hence it fails.
I've also attempted to loop for a number of seconds, or even use a Thread.Sleep(xxxx), but the browser window fails to populate until the sleep or timer stops.
I attempted to use the suggestions found on the following StackOverFlow site shown below.
How to use WebBrowser control DocumentCompleted event in C#?
private void webBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
string url = e.Url.ToString();
if (!(url.StartsWith("http://") || url.StartsWith("https://")))
{
// in AJAX
}
if (e.Url.AbsolutePath != this.webBrowser.Url.AbsolutePath)
{
// IFRAME
}
else
{
// REAL DOCUMENT COMPLETE
}
}
However, in parsing the OuterHtml, nothing is returned in the first two sections, and in the third section, other elements are returned instead of the desired "https://..." link for File Download.
Interestingly, if I use a webBrowser1.ReadyState event, as shown below, and place a MessageBox inside DocumentCompleted, this seems to allow the browser document to complete, because after clicking the OK button, the parsing is successful.
if (webBrowser1.ReadyState == WebBrowserReadyState.Complete)
{
MessageBox.Show("waiting", "CHECKING");
btnMyUrl.PerformClick();
}
However, I then have the difficulty of finding a way to click the OK button of the MessageBox.
Is there another event that occurs after the DocumentCompleted event.
OR, can someone suggest how to programmatically close the MessageBox?
If this can be done in code, then I can perform the buttonClick() of the 2nd button in that section of code.

After finding that the addition of a MessageBox allows the webBrowser1.Document to complete, and using webBrowser1.ReadyState event within the webBrowser_DocumentCompleted event, all I needed to do, was to find a way to programmatically close the MessageBox.
Further searching on StackOverFlow revealed the following solution on the site below.
Close a MessageBox after several seconds
Implementing the AutoClosingMessageBox, and setting a time interval, closed the MessageBox and allowed my button click, i.e. btnMyUrl.PerformClick(); to successfully parse the OuterHtml and now the code works properly.
Hopefully, if someone else discovers that placing a MessageBox within the webBrowser_DocumentCompleted event allows the document to complete; the aforementioned AutoClosingMessageBox will assist them as well.

Why does my modal page have a back button?

Project and problem explanation
In my case I have a page which instructs the user how to move a certain machine. This page is supposed to be a modal page since the page should not be navigated away from without performing or completely canceling the action.
I have a mainpage with a listview which opens the details page of any of the items contained in the listview on click through the onSelect method:
Navigation.PushAsync(new FooPage(string Name)); /* gets called in the
onSelect method if selection is not null*/
The model is retrieved within the details page's viewmodel after passing the name to it and then using a model manager injected into the viewmodel with Unity to retrieve it.
-- we now both have a mainpage and detailspage on the stack which of only the detailspage has a backbutton --
On the detailspage we have a button called "Teach" with a x,y,z field next to it after clicking it this method gets called:
private async Task Button_Clicked(object sender, EventArgs e)
{
await Navigation.PushModalAsync(new ManualTeachPage());
}
which then, as it should, creates the page but then for some reason decides to add a back button to it:
Debugging and Research
This behavior is not visible on Android which does not have a visible back button or navigation bar on this page but does have a backbutton on the Details-page as well.
I have used modal pages before but I have never seen this kind of behavior, I have tried using the Navigation property of the Application.Mainpage itself which resulted in the exact same result except for one case.
I thought it might have something to do with me switching out the Application.Mainpage at one point(there is a stack of tutorial pages the user has to go through), seems like calling the pushModalAsync one line AFTER setting the new mainpage then it DOES push the page as a modal page and performs like one (without a back button) but does not do so after this point.
No bug reports on Bugzilla about this either as far as I have seen, neither have I found anything on the internet about this particular problem.
Note that when clicking the back button on the teachPage it returns to the detailspage. When the teachPage gets pushed it does actually get pushed onto the ModalStack.
update 1
Checked again if the modal page which I was talking about was the only modal page on the modal Stack, it was. NavigationPage.SetHasBackButton(this, false); does not seem to work either as suggested by Diego Rafael Souza.
update 2
I thought I would temporarily disable the backbutton by using the onBackButtonPressed within the teachpage until I had found a solution. Turns out this doesn't work for UWP anymore, this method does not get called anymore on this page or any page for that matter. It does work for the Android Hardware button though.
update 3
I tried using:
SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility =
AppViewBackButtonVisibility.Collapsed;
This does hide the backbutton on UWP but for some reason #if WINDOWS_UWP doesn't work at all. If I do this without the #if the program won't build for Android. No solution yet, not only this but when using this fix the other pages still had the onBackButtonPressed method disabled.
update 4
after updating to the newest version of xamarin forms the OnBackButtonPressed started working again. The backbutton still appears on the page but I now have disabled it.
Recreating the problem
I recreated the problem in this small test project:
https://www.dropbox.com/sh/6btsud3uvw503ee/AAAiaGb3TwhMrZMJb2j-rd36a?dl=0

In your function Button_Clicked() in your example, in page DetailPage, where you call your Modal, right after calling PushModalAsync(new TeachPage());, use:
NavigationPage.SetHasNavigationBar(this, false);
NavigationPage.SetHasBackButton(this, false);
My guess is when you tried using the above SetHasBackButton, you were doing it on the Modal itself, but the back button you were actually seeing came from your DetailPage.
Once you add this, the modal pops up, and the back button disappears. If you set a "Back" button on your modal in order to close it, you can easily get your NavBar and BackButton back in your DetailPage by adding in an OnAppearing() Function in your DetailPage code-behind like so:
protected override void OnAppearing()
{
base.OnAppearing(); // do the usual stuff OnAppearing does
NavigationPage.SetHasNavigationBar(this, true); //get your navbar back
NavigationPage.SetHasBackButton(this, true); //get your back button back
}

What is the event which fires every time when i click outside for my wpf page?

i am developing windows application using wpf. I want to do some functionality when i click outside of my control created. for example, if i have Message-box open in my window, i want to do some function if i click outside of my Message-box window.
I tried,
private void OnPreviewMouseDown(object sender, MouseButtonEventArgs e)
{
.....
}
but its not working.. please any one tell me, what is the event fire when i click outside of my control?

you have two supposed solutions:
one of them is to get Mouse.X, Mouse.Y from System not from application, this article will help
http://www.codeproject.com/Articles/7294/Processing-Global-Mouse-and-Keyboard-Hooks-in-C
second which is better is not using Dialog, but use PopUp window and this article will help
how to close a WPF Dialog Window when the user clicks outside it

Loading ASP.NET user control at run time

I have an ASP.NET user control with a button, and I want to add it to the page when the user clicks a button from another user control. I have created an event handler to the first user control to handle it from the page and add the second user control to a page. Everything is working normally, but the button on the second user control doesn't respond to the event.
I place the second control on RadAjaxPanel
Note: When I add the second user control at design time its working fine.

All dynamically created controls should be added by the end of Page_Init (though sometimes you can get away with them added by the end of Page_Load).
If you're only adding them based on a button click event then you've done this in the event handers which fire AFTER Page_Init and Page_Load in the lifecycle - This is why your events don't fire and why it works fine when you add at design time.
This is because when a button is clicked on the second user control - the whole page lifecycle starts again. The page goes through Page_Load and Page_Init first and your control doesn't get loaded here. So, when the page lifecycle handles the "handle postback events" part, the control no longer actually exists, so the event doesn't fire.
Conversely, when you add at design time, the control exists in Page_Init and Page_Load so is able to handle the postback events from the user control because it already exists in the control tree - if this makes sense.
You need to think how you can restructure so they're added by the time Page_Load has finished at the very latest or it won't work. Without code samples or more detail it's hard to suggest exactly how you might do this. One possibility would be to set it visible instead of loading it outright - but if the control does some 'heavy lifting' on load like database hits or API calls then this might not be suitable for you.
I did something similar. What I did was to load some controls dynamically based on a selection from a DropDownList. If you have a method which loads the control for you, let's call it LoadControls(), then you can do something like this:
DropDownList_Click {
ViewState("LoadControls") = true;
LoadControls()
}
By setting the ViewState variable, you can then indicate Page_Load to load the controls on future postbacks:
Page_Load {
if (ViewState("LoadControls") == "true")
{
LoadControls();
}
}
This has the effect of then loading the control on-the-fly when the event first happens, and then at future times in the lifecycle.

ASP .NET Button event handlers do not fire on the first click, but on the second click after a PostBack

Background: I am customizing an existing ASP .NET / C# application. It has it's own little "framework" and conventions for developers to follow when extending/customizing its functionality. I am currently extending some of it's administrative functionality, to which the framework provides a contract to enforce implementation of the GetAdministrationInterface() method, which returns System.Web.UI.Control. This method is called during the Page_Load() method of the page hosting the GUI interface.
Problem: I have three buttons in my GUI, each of which have been assigned an Event Handler. My administration GUI loads up perfectly fine, but clicking any of the buttons doesn't do what I expect them to do. However, when I click them a second time, the buttons work.
I placed breakpoints at the beginning of each event handler method and stepped through my code. On the first click, none of the event handlers were triggered. On the second click, they fired.
Any ideas?
Example of Button Definition (within GetAdministrationInterface)
public override Control GetAdministrationInterface()
{
// more code...
Button btn = new Button();
btn.Text = "Click Me!";
btn.Click += new EventHandler(Btn_Click);
// more code...
}
Example of Event Handler Method Definition
void Btn_Click(object sender, EventArgs e)
{
// Do Something
}
Page_Load Method that calls GetAdministrationInterface
protected void Page_Load(object sender, System.EventArgs e)
{
if (!Page.IsAsync)
{
List<AdministrationInterface> interfaces = <DATABASE CALL>;
foreach(AdministrationInteface ai in interfaces)
{
placeholderDiv.Controls.Add(ai.GetAdministrationInterface());
}
}
}

Good grief! I knew it was going to be something this stupid. Purely my fault of course and my lack of knowledge in ASP .NET.
After doing a multitude of Google searches and eventually being blocked by Google on suspicion of being a bot running automated scripts, I managed to squeeze in one last search in and stumbled across this article. Already at the point of giving up, I tried my best to read the article without skipping 10 lines at a time or looking for pretty pictures. In the section titled Assigning IDs to Dynamically Created Controls, I read these magical and most joyful words:
If you view the source HTML before you click the not-working button and after you have clicked it, you will notice a small difference. The buttons have different HTML IDs before and after the post-back. I got ctl04 and ctl05 before the post-back and ctl02 and ctl03 after the post-back.
ASP.NET button recognizes events by checking for a value for its ID in the Request.Form collection. (In truth it happens differently and controls do not check Request.Form collection by themselves. Page passes post data to controls by their IDs and to controls that are registered to be notified about post data). ASP.NET does not fire the Click event, because the button's ID has changed between the post-backs. The button you have clicked and the button you see after are different buttons for ASP.NET.
Sure enough, when I viewed the HTML the first time, my button had the ID ctl04$ctl36. After clicking the button, my button had the ID ctl04$ctl33.
So there you have it! All I had to do was set the ID on the buttons and presto! My event handlers are now being called!
Sample Solution:
public override Control GetAdministrationInterface()
{
// more code...
Button btn = new Button();
btn.Text = "Click Me!";
// !!THE BANE OF MY EXISTENCE!!
btn.ID = "The_Bane_of_My_Existence";
// !!THE BANE OF MY EXISTENCE!!
btn.Click += new EventHandler(Btn_Click);
// more code...
}
What a great way to spend two days...

I had the same problem, but the accepted answer here was not causing it. I had a text box and a search button, and clicking the button the first time didn't perform the search. The event handler of the button wasn't being hit. But clicking the button a second time did trigger the event on the server. Here is why:
If you have an <asp:Textbox> with its AutoPostBack set to true, after typing in the text box and then moving to click a button, the text box causes a post-back immediately the moment it loses focus. So the click even of the button doesn't count (the page is already posted-back as a result of the text box's event). That's why when you click the button a second time, it works because the text box is not involved in the second post-back.
Set the AutoPostBackproperty of the <asp:Textbox> to false to fix this issue.

A quick fix is to set an ID to the ASCX control your are loading on a page. For example, if your code is like this:
UserControl SpecsControl = (UserControl)Page.LoadControl("../name.ascx");
SpecsContainer.Controls.Add(SpecsControl);
then you need to add a line (before Controls.Add):
SpecsControl.ID = "Aribtrary_Name";
Then your handler method is fired at the first click.

I was facing the same problem. My button froze after my first click. For me this annoying problem got solved when I disabled the button's EnableViewState attribute.

For me it was the UpdatePanel , my Button and my TextBox were both inside an UpdatePanel , so when I post-back , it caused some weird behavior . It took it outside of the UpdatePanel and that fixed it .

Even i had the same problem. the cause was "localhost:1656/secure/login.aspx?ReturnUrl=%2f".
if the request contain %2f as query string, the first post will not be succeeded even though "%2f" is representing "/".
one way to avoid this by having a condition check in pageload
protected void Page_Load(object sender, EventArgs e)
{
string queryString = Request.QueryString.ToString();
if(queryString == "ReturnUrl=%2f")
{
Response.Redirect("/secure/login.aspx");
}
}

Whilst its hard to know exactly without seeing the full Page_load method it does smell a little bit like the event handlers are not hooking up until the page is reloaded.
eg:
if (IsPostBack) {
// Add handlers here ...
}

I had same problem. And I searched on internet i didnt find a solution. After that i found sample code and I used it. It worked for me. Web site link is below:
http://www.c-sharpcorner.com/UploadFile/abhikumarvatsa/calling-an-Asp-Net-C-Sharp-method-web-method-using-javascript/