static void Main(string[] args)
{
Console.WriteLine("欢迎来到图形工厂，请输入你想要创建的图形:\r\nTriangle代表三角形，Circle代表圆形，\r\nSquare代表正方形，Rectangle代表长方形\r\n输入0可以退出程序");
String graphName = null;
graphName = Console.ReadLine();
GraphFactory factory = new GraphFactory();
Graph graph = null;
while (String.Compare(graphName, "0") != 0)
{
if (String.Compare(graphName, "Triangle") == 0 || String.Compare(graphName, "Circle") == 0 || String.Compare(graphName, "Rectangle") == 0 || String.Compare(graphName, "Square") == 0)
{
graph = factory.createGraph(graphName);
double a = graph.getArea();
Console.WriteLine("面积为： " + graph.getArea());
Console.WriteLine("\r\n请输入你想要创建的图形:(Triangle，Circle，Square，Rectangle,0退出)");
graphName = Console.ReadLine();
}
else
{
Console.WriteLine("输入无效字符，请重新输入有效字符：(Triangle，Circle，Square，Rectangle,0退出)");
graphName = Console.ReadLine();
}
}
}
static void Main(string[] args)
{
Console.WriteLine("请输入图形的名称（正方形、三角形、圆形、长方形）：");
Graph graph = GraphFactory.GetGraph(Console.ReadLine());
graph.Display();
}