Develop Reference

Is there any way to invoke a Cortana response without user input?

I have an app I am working on for Windows 10 which should notify a user when external data reaches a certain threshold.
While I can simply use Windows Notifications (and will fall back on them), I'd really like to do more integration with Cortana. (Voice activation and natural searching will be available.)
Is there any way to have Cortana notify the user when the change is triggered (either with speech or via a new item on her dashboard) without a user specifically asking her?

I was (and still "is", actually) also very interested in this kind of things, but as far as I could see it the only Cortana-related API lives in Windows.ApplicationModel.VoiceCommands namespace and there is nothing there to invoke Cortana, only handle voice command from Cortana.
So, hopefully Microsoft will either extend this or separate namespace in the future OR make Cortana available via cross app communication.

how to make windows startup project with many methods running at the same time in the background

I have explained my project below and asked some questions with "My Question-" tag.
I have working on a project. At the time of windows logon page if I enter a wrong password my cam should take the picture, If I open regedit my system should take a screen shot and save these images in C:\Windows\system32\new folder (I tried a lot making this work with the help of manifest files but failed everytime) and emails it whenever finds an internet connection
I have a form based app because I didn't find any other way to capture image from webcam directly but taking input from pictureBox1.Image.
My cam, screenshot,email (didn't find a way to autocheck if has internet connection available or not) and 3 events checker for "firewall enable/disable, windows logon failure , regedit event called" are done and they are working good.
What I need to do is to assemble these codes to work as an app and running in the background continuously from the time of windows startup to shutdown
To validate positive events I need to make a desktop based db ("My Question"- still figuring out either to choose sql or localdatabase in c#. Please also tell me a suitable solution.I have to delete all the entries from the db once a day is over). The db would contain the following columns (event id, event name, event timestamp).
I want my app to check if this very event exists in the db then it should ignore the event generated on windows event log else it should make a new row with the db columns and it should do the following actions based on the event like taking webcam pic or screenshot.
"My Question"- I want my app to be live at the time of windows logon page. A lot of programs start later when you are authenticated but I need my program to be live at the time of logon page. Do I have to make 1 or many services? or multi-threaded? because in the typical form based app you can only call one function at a time and wait for it to return something or perform some task/action and then you call the second third whatever.
"My Question"- Do I need to use the backgroundworker in c#
Please help!

You have a lot of things going on here for one question.
You can put all your code in a background service that gets started at boot time. There is a walkthrough here to show you how to do that (along with a million other sites).
Addressing some of the other issues you listed:
Google is your friend...
Webcam - Found a quick reference here and here
File Modification - Another SO thread here
SQL vs. Other Database - Not sure you need anything elaborate here, probably something you can put together pretty quickly. Another SO thread addressing that here
Good Luck!

How to monitor different events in 3rd party applications

I am developing a C# application. I am looking for a way to monitor different events in 3rd party applications.
Example 1: Calculator is running, and I want to know when the user has clicked on "=" button.
Example 2: Skype is running and I want to monitor when the user hits the "Call" button.
Example 3: Word is running and I want to monitor when the user opens the "Font" drop down list.
I am not looking for simple Mouse or Keyboard events.

Take a look at EventSpy, Both of those seams to do what you need.
http://www.codeproject.com/Articles/11918/EventSpy
http://eventspy.codeplex.com/

You basically need to tap into the "Windows Messaging" loop. In order to properly filter the GAZILLION messages that come flying through you'll also need to be able to periodically scan through all of the active windows to see which ones (if any) are relevant to you.
Be aware that this whole subsystem of windows is a GIANT security hole. (I have not worked with it much since NT4 / W95/W98 days so they might have tried attempts to "secure" it since then so it might be even harder to get to than it used to be.
You're going to need a good ide / 3rd party tools to help you get started on your way to have some idea of what you're looking for.
In a "previous" life we used this basic technique to get ~4,000 workstations to install their own software, updates, patches, etc through monitoring for existence of certain windows, controls, etc and "injecting" messages into the Windows Messaging loop to control Application Setup Programs, configuration changes that were not stored in the registry, etc, etc...

How to get focused elements of specific process in c#

im stuck in my problem, i have invoke a process and now i want its focused elements.
for example. i run a process www.google.com that opens up in Google chrome
now lets say i want to search "hello" the way of doing this as far as i know is to get the keyboard focus element that will be a textbox of google.com .so how to do that through my application i.e programmatically(getting keyboard focused element of chrome process)
Process[] pr = Process.GetProcessesByName("chrome");
var target = pr[0];

Your question a is a bit vague, so I'll try to give several pointers based on several different interpretations:
1) If the process you're referring to is always a web-site, you should skip the screen-scraping techniques, like #vulkanino mentioned, and simply fetch the contents of the web-site directly. If you must get the website as parsed by a real browser (rather than the raw HTML itself), you can use screen-scraping, but remember that not all computers use the same browser.
2) If you want to screen-scrape information from a running process, you (unfortunately) don't have a simple API like the one you expected, where the Process pr object contains a list of elements you can traverse. This is because the process might have been written in .NET/WinForms, .NET/WPF, C++/MFC or any of a dozen other UI frameworks that work very differently.
What I would suggest is using a screen-reader accessibility framework, such as Microsoft's UI Automation, which is able to extract text from the UI of many common applications. This functionality exists to help read out application UI for the hard of sight, but can be used for screen-scraping as well.

How does someone go about writing a "macro" in C#?

I know something about MACROS. I don't mean the ASSEMBLY language kind. I am talking about those programs that you can use perform repetitions actions on another program. I am talking about those programs that you can use to record a series of events on your computer, like, mouse movements and button clicks and then you can play them back. Some of them are elaborate enough to run only on a paricular app that you designate.
I wrote one of sorts once. It was a program that launched an Excel sessions and then used the dynamic data exchage pipe of some kind to feed the excell session script commands. It worked.
But something on the level of the operating system, I imagine, is a whole different story.
How does someone go about writing a "macro" in C#?
I think the approach I will take is to use the spy routine that comes with the development environment to get a list of the proper messages and parameters (wm_lbuttondown for example) and then use dynamic data exchange to send those messages to the app.
So I have three questions.
Is this the best way to do this?
How do I get a handle to an app that is already running?
How do I send user-like messages to an app that is already running?

There are different answers based on many following factors:
is it 3rd party or your own
application?
does it have automation interface
GUI toolkit used in app
If it is a 3rd party app then you need to work on Windows API level via PInvoke - subclassing WinMain proc, capturing and sending input messages, etc. There are 3rd party library for that task. C# obviously is not a right choice for such task.
In case application has automation model (like Excel) it's a pretty straight forward to write program that will be interact with this app.
If it's your own application you want to enhance with macros functionality then you should take this into account on design state. If you use Command pattern from the beginning then it's not hard to program macro recording.
You should provide more details to get a better answer.
Oh, I almost forgot to answer those three questions
Is this the best way to do this?
Depends on concrete scenario
How do I get a handle to an app that is already running?
Depends on application. If it's a native Win app you can easily get process Id and window's handle via WinApi.
How do I send user-like messages to an app that is already running?
Once again it depends on application type. For native win apps you can easily send WM_XXX messages via WinAPI

Unless its something you need to add in your own program you can just download a keyboard/mouse macro program and use it to perform these repeatable actions.
On the other hand to perform macro's in your own program you would want to find a way to record the buttons clicked and write them to a temporary list that can be saved and then run the list by clicking the buttons (programmically).