Visual C++ .NET/Database ADO.net/SqlConnection

Close database connection in destructor

<source lang="csharp">

1. include "stdafx.h"
2. using "System.dll"
3. using "System.Data.dll"

using namespace System; using namespace System::Data::SqlClient; ref class DataConnection {

  SqlConnection^ conn;
  public:
  DataConnection()
  {
     conn = gcnew SqlConnection("Server=(local);Uid=sa;Pwd=****;Initial Catalog=master");
     conn->Open();
  }

  ~DataConnection()
  {
     this->!DataConnection();
  }
  !DataConnection()
  {
     try {
       Console::WriteLine("Closing connection...");
       conn->Close();
     }
     catch(Exception^ e)
     {
        Console::WriteLine("Error occurred! " + e->Message);
     }
  }

}; int main() {

  DataConnection connection1;
  DataConnection^ connection2 = gcnew DataConnection();
  GC::Collect();

}

 </source>

Make connection to database with SqlConnection

<source lang="csharp">

1. include "stdafx.h"

using namespace System; using namespace System::Data; using namespace System::Data::SqlClient; using namespace System::Configuration; void main() {

   SqlConnection^ connection = gcnew SqlConnection();
 connection->ConnectionString = "SQLConnection";
 try
   {
       connection->Open();
       Console::WriteLine("We got a connection!");
   }
   catch (SqlException ^e)
   {
       Console::WriteLine("No connection the following error occurred: {0}",
           e->Message);
   }
   finally
   {
       connection->Close();
       Console::WriteLine("The connection to the database has been closed");
   }

}

 </source>