是否可以在swift中手动释放静态变量?

Question

我只需要在应用程序启动时存储一次静态变量，并且只需要很短的时间。

Answer 1

是的，静态变量可以用var声明，用?可选，就像实例变量和局部变量一样。

class Y { }
class X {
    static weak var myOptionalStaticThing:Y? = Y()
    func foo() {
        // X.myOptionalStaticThing gets deallocated after this
        // if this were the only strong pointer to X.myOptionalStaticThing
        X.myOptionalStaticThing = nil
    }
}