Shanti's Classwork - Rectangle Class

Code without the implementation for the Point object.
Class Definition for Rectangle:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace RectangleClass
{
    class Rectangle
    {
        //fields
        private int length = 0;
        private int width = 0;
        
        //properties
        public int Length
        {
            get { return length; }
            set { length=value; }
        }
        public int Width
        {
            get { return width; }
            set { width = value; }
        }

        //constructors
        public Rectangle()
        {
        }
        public Rectangle(int _length, int _width)
        {
            length = _length;
            width = _width;
        }

        //methods
        public int getArea()
        {
            return length * width;
        }

        public int getPerimeter()
        {
            return (length + width) * 2;
        }

        public void increaseLength(int _lengthIncrease)
        {
            length = length + _lengthIncrease;
        }

        public void increaseWidth(int _widthIncrease)
        {
            width = width + _widthIncrease;
        }
    }
}

UI Form

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

namespace RectangleClass
{
    public partial class Form1 : Form
    {
        Rectangle myRec1 = new Rectangle(0, 0);

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void btnGetLength_Click(object sender, EventArgs e)
        {
            CheckFields();
            MessageBox.Show("Length is " + myRec1.Length);
        }

        private void btnGetWidth_Click(object sender, EventArgs e)
        {
            MessageBox.Show("Width is " + myRec1.Width);
        }

        private void btnArea_Click(object sender, EventArgs e)
        {
            MessageBox.Show("Area is " + myRec1.getArea());
        }

        private void btnPerimeter_Click(object sender, EventArgs e)
        {
            MessageBox.Show("Area is " + myRec1.getPerimeter());
        }

        private void CheckFields()
        {

            if (txtLengthInc.Text != "")
                myRec1.increaseLength(int.Parse(txtLengthInc.Text));
            if (txtWidthInc.Text != "")
                myRec1.increaseWidth(int.Parse(txtWidthInc.Text));

            if (txtLength.Text != "")
                myRec1.Length = myRec1.Length + int.Parse(txtLength.Text);
            if (txtWidth.Text != "")
                myRec1.Width = myRec1.Width + int.Parse(txtWidth.Text);

        }


    }
}