From this project I will share how to create a constructor or maybe you need for method that use array parameters.

Design of implementation in KNN node class will be like this :

KNNNode node1 = new KNNNode("Rose", 2.5, 4, 4.2);
KNNNode node2 = new KNNNode("Height", 2.5, 4, 4.2, 4.5, 6.3);

So you can add more parameters to that class.

Here my code in KNNNode class :

using System.Collections.Generic;

namespace Algorithm.KNN
{
    public class KNNNode
    {
        List val;
        string label;

        public string Label
        {
            get { return label; }
            set { label = value; }
        }

        // 'params float[] val' it will create array parameters
        public KNNNode(string label, params float[] val)
        {
            //set label
            this.label = label;
            //Set actual size of val
            this.val = new List(val.Length); 

            //iterate from first to last argument
            //and fill to list
            foreach (float v in val)
            {
                this.val.Add(v);
            }
        }

        public int Count
        {
            get {
                return val.Count;
            }
        }

        //prevent default constructor inisialization
        private KNNNode()
        { }

        //Direct access to list value
        public float this[int index]
        {
            get { return val[index]; }
            set { val[index] = value; }
        }
    }
}

Hope it’s help
Willy Achmat Fauzi