1. public class clsPoint
    2.     {
    3.         public double dblX;
    4.         public double dblY;
    5.         public clsPoint() { }
    6.         public clsPoint(double _dblX, double _dblY)
    7.         {
    8.             dblX = _dblX;
    9.             dblY = _dblY;
    10.         }
    11.     }
    12.     public class clsLine : clsPoint
    13.     {
    14.         clsPoint point1, point2;
    15.         public clsLine() { }
    16.         public clsLine(clsPoint _clsPoint1, clsPoint _clsPoint2)
    17.         {
    18.             point1 = _clsPoint1;
    19.             point2 = _clsPoint2;
    20.         }
    21.         public double getDistance()
    22.         {
    23.             double dblDistance, dblDistance1, dblDistance2;
    24.             dblDistance1 = Math.Pow(point1.dblX - point2.dblX, 2.0);
    25.             dblDistance2 = Math.Pow(point1.dblY - point2.dblY, 2.0);
    26.             dblDistance = Math.Sqrt(dblDistance1 + dblDistance2);
    27.             return dblDistance;
    28.         }
    29.     }
    30.     public class clsRect : clsLine
    31.     {
    32.         clsLine line1, line2, line3, line4;
    33.         public clsRect(clsLine _line1, clsLine _line2, clsLine _line3, clsLine _line4)
    34.         {
    35.             line1 = _line1;
    36.             line2 = _line2;
    37.             line3 = _line3;
    38.             line4 = _line4;
    39.         }
    41.         public double getPerimeter()
    42.         {
    43.             double dblPerimeter;
    44.             dblPerimeter = 2 * (line1.getDistance() + line2.getDistance());
    45.             return dblPerimeter;
    46.         }
    48.         public double geteArea()
    49.         {
    50.             double dblArea;
    51.             dblArea = line1.getDistance() * line2.getDistance();
    52.             return dblArea;
    53.         }
    54.     }
    55.     class Program
    56.     {
    57.         static void Main(string[] args)
    58.         {
    59.             clsPoint point1 = new clsPoint(0.0, 10.0);
    60.             clsPoint point2 = new clsPoint(20.0, 10.0);
    61.             clsPoint point3 = new clsPoint(20.0, 0);
    62.             clsPoint point4 = new clsPoint(0.0, 0.0);
    64.             clsLine line1 = new clsLine(point2, point1);
    65.             clsLine line2 = new clsLine(point3, point2);
    66.             clsLine line3 = new clsLine(point4, point3);
    67.             clsLine line4 = new clsLine(point1, point4);
    69.             clsRect rect = new clsRect(line1, line2, line3, line4);
    71.             double dblDistOfLine;
    72.             dblDistOfLine = line1.getDistance();
    73.             Console.WriteLine("两点之间的距离为：" + dblDistOfLine);
    75.             double dblPerimeterOfRect, dblAreaOfRect;
    76.             dblPerimeterOfRect = rect.getPerimeter();
    77.             dblAreaOfRect = rect.geteArea();
    78.             Console.WriteLine("矩形的周长为：" + dblPerimeterOfRect);
    79.             Console.WriteLine("矩形的面积为：" + dblAreaOfRect);
    80.         }
    81.     }