Сергей Соловьев

void CommonLogic(byte[] array)
{
      method_one(array);
      method_two(array);
       /* Основной код */
}
// Вызов этой функции
byte[] common;

switch (name)
{
    case "Bob":
        common = array_bob;
        break;
    case "Tom":
        common = array_tom;
        break;
    case "Sam":
        common  = array_sam;
        break;
}
CommonLogic(common);

Или хотя бы гайды по библиотеке NAudio.

public async Task ApplyRange(Guid pharmacyId, IEnumerable<(Guid id, int count)> products)
{
    await _table.BeginTransactionAsync();
    for (var (id, count) in products)
    {
          await _table.Where(e => e.PharmacyId == pharmacyId && e.ProductId == id)
                              .ExecuteUpdateAsync(entity => entity.SetProperty(x => x.Count, x => x.Count + count))
    }
    await _table.CommitTransactionAsync();
}

var (item, index) = collection.Select((c, i) => (c, i)).First(pair => pair.Item1 == target)

var array2 = new int[,]
{
    { 1, 2 },
    { 3, 4 }
};
var array = Unsafe.As<int[]>(array2);
foreach (var i in array)
{
    Console.WriteLine(i);
}

var array2 = new int[,]
{
    { 1, 2 },
    { 3, 4 }
};
var arrayDst = new int[array2.GetLength(0) * array2.GetLength(1)];
Buffer.BlockCopy(array2, 0, arrayDst, 0, 4 * sizeof(int));