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Using .Net how can I programmatically navigate to a webpage, interact with it via code, then get particular values from a newly generated page

I have a scenario where I would like to automate programmatically the following process:
Currently, I have to manually
Navigate to a webpage
Enter some text (an email) in a certain field on the webpage
Press the 'Search' button, which generates a new page containing a Table with the results on it.
Manually scroll through the generated results table and extract 4 pieces of information.
Is there a way for me to do this from a Desktop WPF App using C# ?
I am aware there is a WebClient type that can download a string, presumably of the content of the webpage, but I don't see how that would help me.
My knowledge of web based stuff is pretty non-existent so I am quite lost how to go about this, or even if this is possible.

I think a web driver is what you're looking for, I would suggest using Selenium, you can navigate to sites and send input or clicks to specific elements in them.

Well, I'll write the algorithm for you but you also need to some homework.
UseWebClient get the htm page with the form you want to auto fill and submit
Us regex and extract the action attribute of the form you want to auto submit. That gets you the URL you want to submit your next request to.
Since you know the fields in that form, create a class corresponding to those fields, let's call the class AutoClass
Create a new instance of your auto class and assign values you want to auto fill
Using WebClient to send your new request with the url you extracted from the form previously, attach your object which you want to send to the server either through serialization or any method.
Send the request and wait for feedback, then further action

Either use a web driver like Puppeteer (Selenium is kinda dead) or use HTTPS protocol to make web requests (if you don't get stopped by bot checks). I feel like your looking for the latter method because there is no reason to use a web driver in this case when a lighter method like HTTP requests can be used.
You can use RestSharp or the built in libraries if you want. Here is a popular thread of the ways to send requests with the libraries built in to C#.
To figure out what you need to send you should use a tool like Fiddler or Chrome Dev Tools (specifically the Network tab) to see what you need to send to acheive your goal as you would in a browser.

How to implement a callback URL to receive a json data in c#

For some days now i have been struggling on a project where i need to provide a URL to enable me to receive a JSON response(precisely this my first time of calling a web API)
This is the scenario:
- First the company has a web service that i need to consume and send a bill prompt to our client and so far it has been successful
- Second , they ask me to implement a callback and give them the URL where they will call me to send the status of the bill whether our client has confirm the bill prompt or not(this is where i am stacked)
When i get the JSON data i can easily use it to do what i want but my problem is how to implement the web page that the company will call to send the status.
Please a sample code will help me a lot.Thanks

What you are trying to achieve is called WebAPI. You expose HTTP endpoints using Controllers to the Internet and consumers of your API may utilize them to POST the status back.

You are describing creating an API. Basically, you create an endpoint url using a controller in C#. It's within this controller that you receive data from "the company" and process it, and do whatever you need to do after that. If you use the standard MVC framework build into C#, it's fairly straight-forward. Here is an example of a callback url we are using in a three-legged OAuth procedure. The last step involves a third party sending a request to our callback url and posting some data. We are using a model as a parameter. But you can use simple structures (int, string, etc) as well. As log as the names of your params match the names that the third party sends in their query string or POST, the MVC framework will handle the variable assignment automatically. The serialization/deserialization is built in to the framework.
Here is a small example of how we have implemented a callback url in one of our apps:
public class MyAuthenticatedController : Controller
{
public ActionResult Index([FromUri]MyAuthenticatedModel model)
{
logTheResponse(model);
if (model == null)
{
throw new HttpException(401, "Auth Failed");
}
}
}
The third party would hit the url:
http://app.mydomain.com/myauthenticated
Using the GET method.

If you don't want to build an ASP.NET Web API Project, you can do this easily with an Azure Function.
See: https://learn.microsoft.com/en-us/azure/azure-functions/functions-create-generic-webhook-triggered-function

How to trigger a snippet of jquery every single page of a web app

Currently I have faced the linguistic problems for my web app. I want to localize my site using Resource.resx , I have finished it already by running a snippet of jquery code recording all text of a page then it pushes to an array and posts to server using ajax . of course I can add to resource programmatically in the server . But the problem now is I dont want to do it each page to store the text then later i can translate . I want a solution that helps me run the application once and I could have all text of it .
Here is the code js .it runs per web request
And here is the code run while js send ajax request to server
It works well if I do request for each page , But i want a solution that i just only run the webapp once and it programmatically records all text of my web app .
thanks for reading !!!

if you want to store information throughtout your application, then you can either look into cookies / Sessions / Html 5 Data api
http://www.w3schools.com/html/html5_webstorage.asp
Global Application Variables:
System.Web.HttpContext.Current.Application.Lock();
System.Web.HttpContext.Current.Application["MyVariable"] = "Value";
System.Web.HttpContext.Current.Application.UnLock();
And you can Access them....
string LicenseName = HttpContext.Application["MyVariable"] as string
However, the most ideal solution would be to store the Data Once into Session / Cookie etc (make call to DB) using a Static Class, and then use this Static Class's member throughout your User's Visit Session. You can't Have the Session Live forever, every new visit need to make at least one DB call (unless you want to use cookies).

I fixed it my self . as you see the script above . I added request urls to the response JSon into the block code running at the server if the ajax sends request . The success callback of ajax can then set window.location.href = theurls . it automatically run my whole web app when i start the application .

Handling Authentication for a File Display using a Web Service

This is my first time developing this kind of system, so many of these concepts are very new to me. Any and all help would be appreciated. I'll try to sum up what I'm doing as efficiently as possible.
Background: I have a web application running AngularJS with Bootstrap. The app communicates with the server and DB through a web service programmed using C#. On the site, users can upload files and reference them later using direct links. There's no restriction to file type (yet), so just about anything is allowed.
My Goal: Having direct links creates a big security problem for me, since the documents/images are supposed to be private data. What I would prefer to do is validate a user's credentials when the link is clicked, then load the file in the browser using a more generic url path.
--Example--
"mysite.com/attachments/1" ---> (Image)
--instead of--
"mysite.com/data/files/importantImg.jpg"
Where I'm At: Not very far. My first thought was to add a page that sends the server request and receives a file byte stream along with mime type that I can reassemble and present to the user. However, I have no idea if this is possible using a web service that sends JSON requests, nor do I have a clue about how the reassembling process would work client-side.
Like I said, I'll take any and all advice. I'd love to learn more about this subject for future projects as well, but for now I just need to be pointed in the right direction.

Your first thought is correct, for it, you need to use the Response object, and more specifically the AddHeader and Write functions. Of course this will be a different page that will only handle file downloads, so it will be perfectly fine in your JSON web service.

I don't think you want to do this with a web service. Just use a regular IHttpHandler to perform the validation and return the data. So you would have the URL "attachments/1" get rewritten to "attachments/download.ashx?id=1". When you've verified access, write the data to the response stream. You can use the Content Disposition header to set the file name.

Creating PDFs on the fly using AJAX & C#

I have a web page.There is a link to generate pdf reports.When the user clicks on the link the pdf generation process should start.Since the file size of the generated pdf is huge(>15Mb) the user cannot wait & thus has to proceed ahead with his other activities.That means the following simultaneous things would be happening now
The PDF Generation process continues unabated
The user continues with browsing without any jolt
After the pdf generation is completed the user should receive an email containing the download link.
Basically the implementation is
User clicks on generate report button
Using AJAX I make a call to the c# function say generateReport()
The problem
When I do this the user is not allowed to perform anything unless & untill the entire process completes.Ofcourse he can click on different links but with no response because of the AJAX call still getting implemented
How do I achieve this.I am a dot net(framework 2.0) developer creating aspx web pages using C#.I use javascript & AJAX(AjaxPro) to get rid of the postback in typical ASP.NET web applications.

In cases like this, you might want to consider splitting your PDF generation code out into a separate service, which your AJAX code could interact with to kick off the PDF creation. Once the service has created the PDF file, the service can email the user with the relevant info.
The AJAX code would use remoting to communicate with the service.

The concept you have in creating the reports and having them emailed to the user is a good one.
The implementation of this should be quite simple on the client side, ie a basic call to indicate that a report needs to be created. ie save this to a table (report queue)
The actual creation of the report should not be triggered by any of the calls from the front-end directly, Create a service (Windows Service) that runs through the "report queue" generating the PDF files and sending the emails.
As an added option, assuming the PDF's are not destroyed (ie not an email only solution) an ajax popup could be created on the client where the user can then go to a reports page and download the already generated file.

You could try on a timer make an AJAX call to a Function isReportDone(), that in turn checks a repository for the PDF. For generating the PDF, I THINK you'll need to pass that task out of your normal Request-Response Thread. Either by calling a seperate Thread (Multi-threading is fun) to process it, or by passing the data out to a seperate service on the server.
These are just two ideas really I had a similar issue with generating a file from a DB that had to be forcibly downloaded. I ended up calling a seperate page, in a seperate window, that wrote the data to the response stream. It actually worked great until the customer's network blocked any and all popups.

User asks for report to be generated (clicks a button)
Page kicks off an async service call to GeneratePdf(args).
User sees a spinner of some sort while Pdf is being generated, that way they know something is happening.
Pdf is generated (iTextSharp might come in handy here).
Pdf is stored somewhere. Database blob field would be ideal, that way the webservice can just pass back the id of the new file. Failing that, pass a filename back to the ajax code.
Webservice async (see this one) complete event happens, ajax code throws up either a popup or redirects to a new page. Maybe you want to replace the spinner with a "Ready!" link.
Link to pdf report file is emailed to user.