Does migrating code from vb.net to a C++ dll offer significant performance boosts?

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• Qt Quick applications not responding

  Any Qt Quick application I compile and run on my Windows 10 desktop with Qt Creator 4.7.2 just hangs after app.exec(). The windows is created with the title specified in the QML file, but nothing else is drawn and the window is "Not responding" .

  I had this happen for my current project I developed first on Linux where it worked fine. On Windows this happens on all Qt Quick applications I tried. The simplest example is New Project -> Qt Quick Application - Empty. I used qmake as build system, Qt 5.11 as version and Desktop Qt 5.11.2 MinGW 32bit as kit.

  I tried reinstalling Qt Creator, using different Qt versions from 5.0 to 5.11 and using MSVC2017 64bit as kit but none worked. Running (Ctrl-R) or running with debugger (F5) or running outside of Qt Creator doesn't change anything.

  Here is the Qt Quick Application - Empty default project with added rectangle to the QML to show that nothing gets drawn.

  main.cpp

  #include <QGuiApplication>
  #include <QQmlApplicationEngine>
  
  int main(int argc, char *argv[])
  {
      QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
  
      QGuiApplication app(argc, argv);
  
      QQmlApplicationEngine engine;
      engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
      if (engine.rootObjects().isEmpty())
          return -1;
  
      return app.exec();
  }
  

  main.qml:

  import QtQuick 2.8
  import QtQuick.Window 2.2
  
  Window {
      visible: true
      width: 640
      height: 480
      title: qsTr("Hello World")
  
      Rectangle {
          anchors.fill: parent
          color: "red"
      }
  }
  

  Result of the example
• Visual Studio 2017 Linux Makefile Project wont build because of chained prefix

  i have a linux project witch i developed in vim and now i'd like to go on developing it in visual studio with intellisense etc.

  its a makefile project so i need to build it on the linux machine.

  i already created the project and created the connection and it works but i cant build because i am building with a prefix script so i open a new interactive shell with something like this

  set -i
  
  . "/tools/dist/xxxx-2010.0"/etc/profile
  

  i dont think that visual studio can handle such thing.

  is there a way to do it.

  i am calling my startprefix script with a alias then it starts the interactive shell and then i enter my make commands for usual but in visual studio it wont build it stops at t he very beginning after executing the first command (which is the startprefix alias)

  and another thing is that i dont see any project files in my solution i unloaded and loaded the project but it wont get me the source files. am i doing something wrong?
• OpenSSL Decryption - EVP_DecryptFinal_ex fails

  I'm using this decryption function to get the plain text value of a cipher which was encrypted using EVP AES 265 GCM; I can see data in rawOut but ret = EVP_DecryptFinal_ex(ctx, rawOut, &len); returns 0; can you provide any insight as to why? I've also seen sources which do rawOut + len in the EVP_DecryptFinal_ex code, I'm not sure why this would be needed as it would move the pointer to the end of the buffer.

  unsigned char* keyDecrypter(unsigned char* pszMasterKey)
  {
      ERR_load_crypto_strings();
  
      int ret, len;
      EVP_CIPHER_CTX* ctx;
      unsigned char* rawOut = new unsigned char[48]; // ToDo Remove Hardcoded Value
  
      Info info = m_header.processKeyInfo();
      if (NULL == info.nonce)
          return NULL;
  
      if (!(ctx = EVP_CIPHER_CTX_new()))
          return NULL;
  
      if (!EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), NULL, pszMasterKey, info.nonce))
          return NULL;
  
      if (!EVP_DecryptUpdate(ctx, NULL, &len, m_header.aad, m_header.aad_len))
          return NULL;
  
      if (!EVP_DecryptUpdate(ctx, rawOut, &len, m_header.encryptedValue, m_header.encryptedValueLen))
          return NULL;
  
      // Finalise the decryption. A positive return value indicates success,
      // anything else is a failure - the plain text is not trustworthy.
      ret = EVP_DecryptFinal_ex(ctx, rawOut, &len);
  
      ERR_print_errors_fp(stderr);
  
      EVP_CIPHER_CTX_free(ctx);
  
      if (ret > 0)
      {
          return rawOut;
      }
      else
      {
          return NULL;
      }
  }
  
• Custom cursor without using .Cur file in WPF

  The code in the following link works great for Winform application.

  https://www.codeproject.com/Tips/60379/Use-Icons-for-cursors-not-CUR

  I am getting following error message with WPF application.

  has unsupported extension for cursor.

  Why do you think the code works for Winform but not WPF?
• Retrieve API JSON (https) with VB.NET (ERROR: Canceled the request: Unable to create a secure SSL / TLS channel)

  I'm trying to query an API from my vb.net code but at the time of executing the "GetResponse" it gives the error "Canceled the request: Unable to create a secure SSL / TLS channel"

  I have modified many things of the code tried to solve my problem but nothing works ...

  I attach the code that I have to see if someone can fix it

      Dim request As HttpWebRequest = HttpWebRequest.Create("https://api.flightstats.com/flex/schedules/rest/v1/json/flight/AA/1917/departing/2018/11/19?appId=583f892b&appKey=e960901ec7dcb40321306743b7a364d0")
      request.Proxy = Nothing
      request.UserAgent = "Test"
  
      ServicePointManager.ServerCertificateValidationCallback = AddressOf AcceptAllCertifications
  
      Dim response As HttpWebResponse = request.GetResponse
      Dim response_stream As System.IO.Stream = response.GetResponseStream
  
      Dim stream_reader As New System.IO.StreamReader(response_stream)
      Dim Data As String = stream_reader.ReadToEnd
      stream_reader.Close()
  
      MsgBox(Data)
  

  _

  Public Function AcceptAllCertifications(ByVal sender As Object, ByVal certification As System.Security.Cryptography.X509Certificates.X509Certificate, ByVal chain As System.Security.Cryptography.X509Certificates.X509Chain, ByVal sslPolicyErrors As System.Net.Security.SslPolicyErrors) As Boolean
      Return True
  End Function
  

  In the code you have the address of the api tal as I want to consult it
• How to append a 2d array with a 1d array in VB?

  I'm having difficulties to find a way to add 1d array to a 2d array in VB. For example:

  Dim arr(,) As Integer
  arr = { {0, 1}, {2, 3}, {4, 5} }
  arr{3} = {6, 7}
  'Now arr should be = { {0, 1}, {2, 3}, {4, 5}, {6, 7} }
  

  Note that the code above is just a demonstration on what I want to achieve, it doesn't work.

  I have been trying things suggested on forum such as:

  1. ReDim Preserve
  2. Array.Resize
  3. Making 2d loop to copy everysingle element to a new variable and add new element then ReDim it back to arr

  All I tried, but they all doesn't seem to work. At the end of the day, I'm looking for a subroutine that could append an 2d array of unknown length for example:

  Dim arr(,) As Integer
  append(arr, {0, 1})
  append(arr, {2, 3})
  'Now arr should be = {{0, 1}, {2, 3}}
  
• Monoose DeprecationWarning collection.ensureIndex and useNewUrlParser

  If you facing problem in mongoose while creating connection with following two warning: 1. DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes instead. 2. DeprecationWarning: useNewUrlParser: true

  Then you can use use following two line of code to avoid this issue:

  mongoose.set('useNewUrlParser',true);
  mongoose.set('useCreateIndex',true);
  mongoose.connect(dbURI)
  .then(connection => {
    console.log('Connected to MongoDB DB')
  })
  .catch(error => {
  console.log(error.message)
  })
  
• I would try to have a performance analysis of my websites

  I have two websites made by me. They are the same, but I used two different technologies: Node.js and PHP, does anybody know how can i have a comparison of these two languages? I would like to have a performance analysis.

  An example: "If the project is made in Node.js, it's faster o slower than PHP?" Also a single analysis for everyone could be good.

  Thank you.
• How many extra hits does my website get if I use Facebook comments or Like buttons on it?

  On our website we have have thousands of stories, and like to show Facebook comments for each one, so readers can discuss. We also have a Like button to make sharing easy.

  When we create a new story and have a look at it ourselves, the Facebook script we use on our page informs the Facebook server, and they then realise they have never seen this particular page before. Their server then makes a new HTTP request for our page, so Facebook can collect some information about it. This is totally separate from the response/activity of the script at our end.

  At this point, we know that this webpage has only ever been seen once...yet the logs will show two hits. Any banner adverts we have on that page will register an extra hit, and so on. No big deal, yet.

  What happens later on, say when the first 10 or 1000 readers view our website to read the story? Obviously the script at our end will go off and grab the Facebook comments, to show them on screen. But will Facebook ever make their own request for our page again, or will they never need to?

  I just want to know how many extra hits are likely to come from the Facebook bot. If there are a lot, maybe I should be detecting the HTTP_USER_AGENT and skip the database calls which generate banner adverts, to reduce load on the server and keep the stats more accurate.

  (I have the same question for the 'Like' button, but I assume that has no need to behave in the same way.)
• how to load 'php_v8js.dll' library file.. I want steps to load it.. I want this file for server side rendering

  I want to load 'php_v8js.dll' library file in my Xampp folder.. I want this file for server side rendering..

  I try to add this file but got warning...

  PHP Warning: PHP Startup: Unable to load dynamic library 'php_v8js.dll'

  I Did following changes in my xampp

  IN  \php\ folder: I added below 3 files
  
   1)   v8.dll
  
   2)   icui18n.dll (php7)
  
   3)   icuuc.dll (php7)
  

  And

  IN \php\ext\ folder: I added 
  
  php_v8js.dll <- this files here.
  
  then made below change in php.ini file
  
  ; V8 Javascript Engine Module
  extension=php_v8js.dll
  

  then I restart my server then also i give same error

  "Class 'V8Js' not found"

  MY PHP Configuration set to :

  Php =>7.2.11
  System  Windows => NT DESKTOP-1067LL0 10.0 build 17134 (Windows 10) i586
  Build Date =>   Oct 10 2018 02:03:59
  Compiler    =>MSVC15 (Visual C++ 2017)
  Architecture    =>x86 
  

  Is it correct what I did in above steps..

  Whats I did wrong in above steps ?? ...

  Please give me proper steps to how to add 'php_v8js.dll' file or for server side rendering what should I required to do.. is this file is necessary to add in xampp folder or not..
• How to create a library in C# to use with unity

  I am trying to figure out exactly how to create a library in C# to use inside Unity, as a plugin really. I have found some instructions on how to do it here: https://www.tristancartledge.com/setting-up-and-building-a-unity-class-library/ but I find some of these instructions are too vague, also I am using visual studio 2017 to build the library. has anyone built a plugin for unity with visual studio 2017 who can give some clear instructions on how to do so?
• Register tlb file windows 10 incompatible version

  I have the following problem: I am about to try to register a tlb with regsvr32. My system is windows 10 64x

  I tried the regsvr32 of the system32 directory and the syswow64 directory but always the following error message:

  The module "% 1" may not be compatible with the Windows version of your computer. Verify that the module is compatible with an x86 (32-bit) or x64 (64-bit) version of regsvr32.exe.

  Any ideas?