How can I catch UniqueKey Violation exceptions with EF6 and SQL Server?

With EF6 and the DbContext API (for SQL Server), I’m currently using this piece of code:

try
{
  // Some DB access
}
catch (Exception ex)
{
  HandleException(ex);
}

public virtual void HandleException(Exception exception)
{
  if (exception is DbUpdateConcurrencyException concurrencyEx)
  {
    // A custom exception of yours for concurrency issues
    throw new ConcurrencyException();
  }
  else if (exception is DbUpdateException dbUpdateEx)
  {
    if (dbUpdateEx.InnerException != null
            && dbUpdateEx.InnerException.InnerException != null)
    {
      if (dbUpdateEx.InnerException.InnerException is SqlException sqlException)
      {
        switch (sqlException.Number)
        {
          case 2627:  // Unique constraint error
          case 547:   // Constraint check violation
          case 2601:  // Duplicated key row error
                      // Constraint violation exception
            // A custom exception of yours for concurrency issues
            throw new ConcurrencyException();
          default:
            // A custom exception of yours for other DB issues
            throw new DatabaseAccessException(
              dbUpdateEx.Message, dbUpdateEx.InnerException);
        }
      }

      throw new DatabaseAccessException(dbUpdateEx.Message, dbUpdateEx.InnerException);
    }
  }

  // If we're here then no exception has been thrown
  // So add another piece of code below for other exceptions not yet handled...
}

As you mentioned UpdateException, I’m assuming you’re using the ObjectContext API, but it should be similar.