Chris 的回答是正确的，如果您确实需要通过引用传递可变的 DateTime.但是，在 F# 中使用编译器将尾随 out 参数视为元组返回值的能力更为惯用:

Chris's answer is correct if you really need to pass a mutable DateTime by reference. However, it is much more idiomatic in F# to use the compiler's ability to treat trailing out parameters as tupled return values:

let couldParse, parsedDate = System.DateTime.TryParse("11/27/2012")

这里，第一个值是 bool 返回值，而第二个值是分配的 out 参数.

Here, the first value is the bool return value, while the second is the assigned out parameter.