COP-17/WinFormsProject/WinFormsLibrary/NumberTextBox.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WinFormsLibrary
{
    public partial class NumberTextBox : UserControl
    {
        public int? maxValue = null;
        public int? minValue = null;
        public string errorText = "";

        public NumberTextBox()
        {
            InitializeComponent();

        }

        public int? MinValue
        {
            get { return minValue; }
            set
            {
                if (value == null) return;
                minValue = value;
                numericUpDown.Minimum = (int)value;
            }
        }

        public int? MaxValue
        {
            get { return maxValue; }
            set
            {
                if (value == null) return;
                maxValue = value;
                numericUpDown.Maximum = (int)value;
            }
        }

        public decimal? Value
        {
            get {
                if (CheckRanges(numericUpDown.Value))
                {
                    return numericUpDown.Value;
                }
                else
                {
                    return null;
                }
            }
            set
            {
                if (CheckRanges(value))
                {
                    numericUpDown.Value = (decimal)value;
                }
            }
        }

        private bool CheckRanges(decimal? value) 
        {
            if (MinValue == null || MaxValue == null)
            {
                errorText = "Ошибка, диапазоны не заданы.";
                return false;
            }

            if (value < MinValue || value > MaxValue)
            {
                errorText = "Ошибка, значение не входит в заданный диапазон.";
                return false;
            }

            errorText = "Ошибок нет.";
            return true;
        }

        public event EventHandler DateChanged
        {
            add { numericUpDown.ValueChanged += value; }
            remove { numericUpDown.ValueChanged -= value; }
        }
    }
}