Swift 3: 'Int' 类型的表达式模式无法匹配 'UnsafeMutableRawPointer' 类型的值

Swift 3: expression pattern of type 'Int' cannot match values of type 'UnsafeMutableRawPointer'

我正在将一个应用程序迁移到 Swift 3,但 Xcode 使用此函数时出现错误:

错误是在案例条件下("contentSize",MyObservationContext) 我这样做是为了更新 uiwebview

的内容大小
var MyObservationContext = 0
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
    guard let keyPath = keyPath else {
        super.observeValue(forKeyPath: nil, of: object, change: change, context: context)
        return
    }
    switch (keyPath, context) {
    case("contentSize", MyObservationContext):
        webviewHeightConstraint.constant = TextoHtml.scrollView.contentSize.height
    default:
        super.observeValue(forKeyPath: keyPath, of: object, change: change, context: context)
    }
}

我愿意接受建议,谢谢。

案例需要

case("contentSize", .some(&MyObservationContext)):

.some是为了确保上下文不为nil

& 获取指向 MyObservationContext 的指针,因此它可以将指针与指针进行比较。