如何删除多个IF-ELSE或重复的三元操作

Question

我想使用干原理来制作以下功能。

private void DetermineLeftAndRightPoint(Coordinate coordinate1, Coordinate coordinate2)
{
    // If false, then parallel to Y axis
    if (IsParallelToXAxis == true)
    {
        LeftPoint = coordinate1.X < coordinate2.X ? coordinate1 : coordinate2;
        RightPoint = coordinate1.X < coordinate2.X ? coordinate2 : coordinate1;
        return;
    }
    LeftPoint = coordinate1.Y < coordinate2.Y ? coordinate1 : coordinate2;
    RightPoint = coordinate1.Y < coordinate2.Y ? coordinate2 : coordinate1;
}

我尝试创建另一个功能，其中使用" out"参数来确定何时平行于x或y的段段的左右点，但是然后，我不得不使用if-else选择x/y参数。有没有更好的写入功能的方法？

Answer 1

，而不是实现out参数，if else和Tirnary Operators我建议提取A class 我们可以放置所有相应的逻辑：

public enum ParallelToAxis {
  None,
  X,
  Y 
}
public class Segment {
  public Segment(Coordinate left, Coordinate right)
    : this(left, right, ParallelToXAxis.None); 
  public Segment(Coordinate left, Coordinate right, ParallelToAxis kind) {
    // Should we swap left and right?
    if (kind == ParallelToAxis.X && left.X > right.X ||
        kind == ParallelToAxis.Y && left.Y > right.Y) {
      Left = right;
      Right = left; 
    }
    else { 
      Left = left;
      Right = right;
    }
  }
  public Coordinate Left {get;}
  public Coordinate Right {get;} 
  ...
  //TODO: Implement Equals, GetHashCode, ToString() etc.  
}

然后您可以简单地放置

private void DetermineLeftAndRightPoint(Coordinate coordinate1, Coordinate coordinate2)
{
    Segment seg = new Segment(
      coordinate1, 
      coordinate2, 
      IsParallelToXAxis ? ParallelToAxis.X | ParallelToAxis.None);
    LeftPoint = seg.Left;
    RightPoint = seg.Right;
}

您可以进一步摆脱LeftPoint和RightPoint的单个Segment属性