问题描述
考虑以下代码:
if (xPoint > 0 && yPoint > 0) { m_navigations = Directions.SouthEast; } else if (xPoint > 0 && yPoint < 0) { m_navigations = Directions.NorthEast; } else if (xPoint < 0 && yPoint > 0) { m_navigations = Directions.SouthWest; } else if (xPoint < 0 && yPoint < 0) { m_navigations = Directions.NorthWest; } else if (xPoint == 0 && yPoint < 0) { m_navigations = Directions.North; } else if (xPoint == 0 && yPoint > 0) { m_navigations = Directions.South; } else if (xPoint > 0 && yPoint == 0) { m_navigations = Directions.East; } else if (xPoint < 0 && yPoint == 0) { m_navigations = Directions.West; }
这很丑陋,我想使用 switch case ,但是如何将 switch 与 2 变量一起使用?
This is quite ugly , and I want to use switch case , but how can I use switch with 2 variables ?
我想过类似 this - @Frits van Campen 的答案,但我需要使用 > 和 < 运算符...
I thought about something like this - the answer of @Frits van Campen , but I need to use > and < operators ...
谢谢
推荐答案
你可以用枚举做任何事情.我为前两个值创建了示例,您可以继续其余的.
You can do everything with enums. I created examples for the first two values, you can continue with the rest.
public enum Direction { SouthEast(1,1), NorthEast(1,-1); int _xPoint, _yPoint; Direction(int xPoint, int yPoint) { _xPoint = xPoint; _yPoint = yPoint; } public static Direction getDirectionByPoints(int xPoint, int yPoint) { for (Direction direction : Direction.values()) { if( Integer.signum(xPoint) == direction._xPoint && Integer.signum(yPoint) == direction._yPoint ) { return direction; } } throw new IllegalStateException("No suitable Direction found"); } }
所以你可以打电话:
m_navigations = Direction.getDirectionByPoints(xPoint,yPoint);