Split string into three pieces?

I have this code maybe help you:

 void Start()
     {
         //packed
         float[] pos = {transform.position.x, transform.position.y, transform.position.z};
         string posINstring = Joinsfloats(pos);
         print(posINstring);
 
         //read packed
         float[] newpos = Split_floats(posINstring);
         transform.position = new Vector3(newpos[0], newpos[1], newpos[2]);
         print(transform.position);
     }
 
     public string Joinsfloats(float[] ar)
     {
         return System.String.Join("_", new List<float>(ar).ConvertAll(i => i.ToString()).ToArray());
     }
 
     public float[] Split_floats(string tx)
     {
         List<float> lista = new List<float>();
         int lasti = 0;
         while (lasti < tx.Length)
         {
             int index = tx.IndexOf('_', lasti);
             if (index != -1)
             {
                 float num = float.Parse(tx.Substring(lasti, index - lasti));
                 lista.Add(num);
                 lasti = index + 1;
             }
             else
             {
                 float num = float.Parse(tx.Substring(lasti, tx.Length - lasti));
                 lista.Add(num);
                 lasti = tx.Length;
             }
         }
         return lista.ToArray();
     }