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Create Excel file in Universal Windows App or in Window Store App

I am learning to develop universal windows 10 app using visual studio 2015. I want to implement a function to create an Excel file then write data in this excel file, in my app. I try to develop it in C# adding reference Microsoft.Office.Interop.Excel.
Generate Error: Missing compiler required member System.Runtime.InteropServices.LCIDConversionAttribute
Search this error and find windows store apps doesn't support Microsoft.Office.Interop.Excel.
I am not able to create Excel file. I do not want to use any commercial library (like syncfusion) for this.
How Can I create Excel file in Universal Windows App or in Window storeApp? Please request to tell me any solution.
Thanks

You will not be able to use the Excel interop libraries in a Windows 10 Universal App. The interop is only available on Windows Desktop, and also requires a dependency on another software (Excel) to be installed on the machine. Both of those are somewhat against the spirit (and more importantly, the technology) of the Universal app.
That being said: If all you need is to generate a file (rather than display it), the general solution is to use something like the OpenXML SDK, which also has the advantage of not requiring Excel on the running machine. Admittedly, the OpenXML SDK doesn't look like it's available for the Universal platform either (see here), but you may find a 3rd-party component that is. Or, if you are OK with requiring internet connectivity, you could create a web service that you send data to, and that processes it and creates the file on your behalf (quite a common pattern, with the additional advantage of protecting your intellectual property behind your own web server). The Interop libraries are much more about automating user actions, are were initially build more for use with VBA/VSTO/COM add-ins, where the interactivity was very much part of the experience. If all you're doing is using the Interop to drive the creation of documents, OpenXML would be the better way to go.
Hope this helps!

OPOS PosExplorer.GetDevice() returns null in .net 4.5 environment?

OPOS PosExplorer.GetDevice() returns null when executed in Windows Service
the source above seems to have so few response, so i was hoping there could be an elaborate explanation/link that can help us on how to implement the security for opos setup?
We are using the same device Epson TM-U220B.

I realise this is a reasonably old post but i'll add a bit of information for starters. If you're still searching for an active solution I can try and shed some more light om the topic.
Have you installed the OPOS Common Control Objects (CCOs)? I recommend checking out Curtiss Monroe's website (http://monroecs.com/oposccos_current.htm).
Once installed, register the ActiveX COM-Objects you desire with regsvr32 and try running your application again.
Let me know how it goes. A.

With a lot of search and ask Microsoft forums, they provide a patch for this problem.
Download this patch from Microsoft and solve this!
http://www.microsoft.com/en-us/download/confirmation.aspx?id=34799
I use the EPSON TM-T20II and .NET 4.5 Framework and it Works!
Let me know if this solved your problem.
Regards!

Face detection for C# in ASP.NET

I'm looking for a specific form of facial recognition. I want to detect where all the faces are located (and that's all) on an image of students in a class-picture.
So in other words, I'm not trying to compare two faces and see if they match either.
How can I do this in C#? I can't seem to find any open-source projects on NuGet regarding this, and I've looked on CodePlex too.

My personal preference for any Computer Vision related needs is to use http://opencv.willowgarage.com/wiki/ , however, it isn't natively made for C#.
However, after a quick Google search, I found http://www.emgu.com/wiki/index.php/Main_Page which says "Emgu CV is a cross platform .Net wrapper to the Intel OpenCV image processing library. Allowing OpenCV functions to be called from .NET compatible languages such as C#, VB, VC++, IronPython etc. The wrapper can be compiled in Mono and run on Linux / Mac OS X."

Now that Face has retired since it was purchased by Facebook, I use Sky Biometry, which has a C# .NET API and is free.
It's cloud based and obviously requires an Internet connection, but who cares.

I recommend checking FaceRecognition.Net (https://github.com/takuya-takeuchi/FaceRecognitionDotNet) that is base on Face Recognition (https://github.com/ageitgey/face_recognition) that is implemented in Python. Both are Open Source with MIT license.
Another option is Cognitive Services – Face that is from Microsoft and you can use it from Azure directly or from a local Docker. Here you can find more about it: https://learn.microsoft.com/en-us/azure/cognitive-services/face/

how use java applet in asp.net without installing java runtime?

i am new in java applet ...
where can i learn more about java applet (related to asp.net) and is it possible to use java applet in asp.net without installing java run time ?
mean is there a library for java on the net that we can refer it ?
(how ?)
for example how can i use below java applet codes without forcing my users to install some thing on their machines?
How to find client computer name in java script/jsp?
mean Júlio Santos answer
thanks in advance

The example you mentioned uses ActiveX (built into IE) and JScript (also built into IE). You do not need the Java Virtual Machine to be installed for that.
In general, running a Java Applet in ASP.NET does not make sense because Applets are client side (they run in the browser) while ASP.NET is (mainly) server side. You can use IKVM to compile the Applet into something .NET understands but that basically gives you access to its public methods which may or may not help depending on your use case.
Here's how you can have IE auto install the JVM runtime: http://java.sun.com/developer/technicalArticles/JavaLP/javawebstart/AutoInstall.html

You cannot use Java without having the runtime installed.
The easiest way to do so, is to let the user navigate to java.com.

C# and .NET FOLDERID

How do I use Windows Vista's FOLDERID API in order to retrieve filepaths for "known folders" such as System or Windows? I've seen some APIs but I don't know how to import them properly. And yes, I know this is a very newbie question, but I spent a half hour googling and couldn't find the answer; I'd also appreciate a way to find an answer to questions like this in the future. :-)
Edit 1: So apparently the relevant functions are included inside of a DLL, and not any "proper" C# class/library that can be imported. The pinvoke syntax might work, although I was hoping for an OOP interface, not a function. Will test.
Edit 2: So I am very new to C# and don't know what a managed interface is. System.Environment.GetFolderPath is perfect.

Take a look at PInvoke SHGetKnownFolderPath
There's also a managed API:
Environment.GetFolderPath
but it doesn't contain all the folders.

This morning I read about Vista Bridge. It may help.
"Many of you don’t know about the Vista Bridge sample library, what can it do or even where you can find it. Let’s start with the basics; i.e. definitions. Vista Bridge is a sample library that contains managed wrappers for a number of Windows Vista APIs that are not exposed in the .NET Framework. The wrappers include common Open and Save file dialogs and new Vista advanced task dialogs. So, where to download it? There are three ways to obtain the sample library. It’s included in both the Windows SDK for Windows Vista Update and in the newer Window SDK for Windows Server 2008 and .Net Framework 3.5; or a third option is to download the Vista Bridge sample library which is part of the Windows SDK Cross Technology samples. I recommend downloading the Windows SDK for Windows Server 2008 and .Net Framework 3.5, but if you don’t have the network bandwidth or just want the samples, then the last option should be the most suitable.
..."