Get neighbors of one particular cell defined by x and y index

Grid.cs

    public int[] GetStatusOfCellNeighbors(int xIndex, int yIndex)
    {
        // Use x from left to right, y from bottom to top
        // 2,0 2,1, 2,2
        // 1,0 1,1, 1,2
        // 0,0 0,1, 0,2

        (int, int)[] GetIndicesOfNeighbors()
        {
            return new (int, int)[]
            {
                (-1, +1), (0, +1),   (+1, +1),
                (-1,  0), /* self */ (+1,  0),
                (-1, -1), (0, -1),   (+1, -1)
            };
        }

        var neighborIndexPairs = GetIndicesOfNeighbors();

        // This may not always be count of 8 as there are cases near boundary
        // So using dynamic list instead of array
        var statusOfNeighbors = new List<int>();
        for (var i = 0; i < neighborIndexPairs.Length; ++i)
        {
            var (x, y) = neighborIndexPairs[i];
            
            // Check if the index of neighbor is valid
            var adjustedXIndex = x + xIndex;
            var adjustedYIndex = y + yIndex;

            if (adjustedXIndex < 0 || adjustedYIndex < 0)
            {
                // adjustedXIndex means out of left board boundary
                // adjustedYIndex means out of bottom board boundary
            }
            else if (adjustedXIndex >= width || adjustedYIndex >= height)
            {
                // Use equal because it is 0 base
                // adjustedXIndex means out of right board boundary
                // adjustedYIndex means out of up board boundary
            }
            else
            {
                // Valid index
                var gridCell = _gridCells[adjustedXIndex, adjustedYIndex];
                var status = gridCell.Status;
                statusOfNeighbors.Add(status);
            }
        }

        // However at returning, need to return array to satisfy return type 
        return statusOfNeighbors.ToArray();
    }