c# - 如何验证重载构造函数的输入？

Question

这是我的代码

public class MyClass
{
    int LeftPoints;
    int RightPoints;

    public MyClass(int points)
        : this (points, points)
    {
        if (points < 0)
            throw new ArgumentOutOfRangeException("points must be positive");
    }

    public MyClass(int leftPoints, int rightPoints)
    {
        if (leftPoints < 0)
            throw new ArgumentOutOfRangeException("leftPoints must be positive");
        if (rightPoints < 0)
            throw new ArgumentOutOfRangeException("rightPoints must be positive");
    }
}

很明显，如果我调用new MyClass(-1)，它会抛出消息“leftPoints 必须为正”。

可以使用 : this (points,points) 重载第一个构造函数并且仍然获得“正确的”验证吗？

Answer 1

您无法通过从第一个构造函数调用第二个构造函数来实现这一点。

如果您追求的是代码重用，则可以采取不同的方法:

public MyClass(int points)
{
    if (points < 0)
        throw new ArgumentOutOfRangeException("points must be positive");
    Init(points, points);
}

public MyClass(int leftPoints, int rightPoints)
{
    if (leftPoints < 0)
        throw new ArgumentOutOfRangeException("leftPoints must be positive");
    if (rightPoints < 0)
        throw new ArgumentOutOfRangeException("rightPoints must be positive");
    Init(leftPoints, rightPoints);
}

private void Init(int leftPoints, int rightPoints)
{
    LeftPoints = leftPoints;
    RightPoints = rightPoints;
}