C# - 如何比较多个可空值以检查那些具有值的值是否相等？

Question

检查多个可为空值以了解非空值是否相等的最简单方法是什么？

double? a = null
double? b = 2;
double? c = 3.5;

应该返回 false

double? a = 2.5
double? b = 2;
double? c = 2;

应该返回 false

double? a = null
double? b = 2;
double? c = 2;

应该返回true

double? a = 4.5;
double? b = 4.5;
double? c = 4.5;

应该返回true

Answer 1

这对我来说似乎相当“简单”：

bool NotNullAllEqual(params double?[] inputs) =>
    inputs.Where(y => y != null).Distinct().Count() == 1;