Dictionary<int, AAA> kv = new Dictionary<int, AAA> {
{ 1, new AAA() { Val = "abc" } }
};
if (kv.TryGetValue(1, out AAA val)) {
val = new AAA() { Val = "efg" }; //这样是错误的
kv[1] = new AAA() { Val = "efg" }; //这样才是对的
}
原文：https://www.cnblogs.com/luludongxu/p/14982092.html