{
    class Problems
    {
        List<Problem> allProblems;
        public string sugprice;
        public Problems()
        {
            allProblems = new List<Problem>();
            allProblems = readProblems();
        }
 
        public List<Problem> readProblems()
        {
            List<Problem> spisok = new List<Problem>();
            foreach (string line in File.ReadLines(@"problems.txt", Encoding.UTF8))
            {
                string[] pr = line.Split(new string[] { "-||-" }, StringSplitOptions.None);
                Problem temp = new Problem(pr[0], pr[1], pr[2]);
                spisok.Add(temp);
            }
            return spisok;
        }
        public List<Problem> getProblems()
        {
            return allProblems;
        }
        public Problem findByProb(string str)
        {
            Problem temp = allProblems.Find(x => x.prob == str);
            return temp;
        }
        public void saveProblems()
        {
            StreamWriter afile = new StreamWriter("problems.txt", false, Encoding.UTF8);
            foreach (Problem p in allProblems)
            {
                afile.WriteLine("{0}-||-{1}-||-{2}", p.ID, p.prob, p.sugprice);
            }
            afile.Close();
        }
 
        public Problem findByID(int ID)
        {
            return allProblems.Find(x => x.ID == ID);
        }
    }
    class Problem
    {
        public int ID;
        public string prob;
        public string sugprice;
        public Problem(string ID, string prob, string sugprice)
        {
            this.ID = Int32.Parse(ID);
            this.prob = prob;
            this.sugprice = sugprice;
        }
    }
}
 
private void buildProblemsBox() // формируем выпадающий список
        {
            foreach (Problem p in problems.getProblems()) // Функция возвращает текущий список проблем 
            {
                problemCombo.Items.Add(p.prob +"  "+ p.sugprice);
            }
        }
 
private void problemCombo_SelectedIndexChanged(object sender, EventArgs e)
        {
             priceBox.Text = p.sugprice;
 
        }
 

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