在python中，当对象可能为None时，如何检查两个对象具有相同的属性值？
我有两个对象，我想检查它们是否具有相同的属性值。但是对象可以是 None。我有以下代码。除此之外，做同样的工作会更简单吗？
if obj1 is None and obj2 is None:
return True
if obj1 is None and obj2 is not None:
return False
if obj1 is not None and obj2 is None:
return False
if obj1.val != obj2.val:
return False
回答
整个事情归结为：
if obj1 is None or obj2 is None:
return obj1 is obj2 # we know at least one is None; are they both None?
return obj1.val == obj2.val # both are definitely not None, compare vals
if obj1 is None or obj2 is None:
return obj1 is obj2 # we know at least one is None; are they both None?
return obj1.val == obj2.val # both are definitely not None, compare vals
测试一下：
作为实际应用，这可以用作递归算法的一部分，以确定两个二叉树是否相同，如Leetcode: Same Tree。这可能解释了为什么您的最后一个条件obj1.val == obj2.valcase 丢失了，因为那是您的递归案例。
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