SwiftReflection
获取从NSObject继承的类的属性的名称和类型。您不需要该类的实例。
用法
SwiftReflection依赖于Objective-C方法class_copyPropertyList来检索从NSObject继承的类的名称和类型。如果您创建了一个Book类
class Book: NSObject {
let title: String
let author: String?
let numberOfPages: Int
let released: Date
let isPocket: Bool
init(title: String, author: String?, numberOfPages: Int, released: Date, isPocket: Bool) {
self.title = title
self.author = author
self.numberOfPages = numberOfPages
self.released = released
self.isPocket = isPocket
}
}Swift Reflection可以使用getTypesOfProperties:inClass类方法检查该类的五个属性。以下检查Book类属性的代码将在下面产生注释打印
guard let types = getTypesOfProperties(inClass: Book.self) else { return }
for (name, type) in types {
print("'\(name)' has type '\(type)'")
}
// Prints:
// 'title' has type 'NSString'
// 'numberOfPages' has type 'Int'
// 'author' has type 'NSString'
// 'released' has type 'NSDate'
// 'isPocket' has type 'Bool'原始数据类型支持
检查哪些属性类型继承自NSObject与其他检查值类型（例如Bool, Int）属性的检查之间存在差异。如果您声明这个比较操作符，您也可以检查值类型
func ==(rhs: Any, lhs: Any) -> Bool {
let rhsType: String = "\(rhs)"
let lhsType: String = "\(lhs)"
let same = rhsType == lhsType
return same
}现在可以使用以下方法检查书籍
func checkPropertiesOfBook() {
guard let types = getTypesOfProperties(inClass: Book.self) else { return }
for (name, type) in types {
if let objectType = type as? NSObject.Type {
if objectType == NSDate.self {
print("found NSDate")
}
} else {
if type == Int.self {
print("found int")
}
}
}
}限制
我还没有能够为以下情况的项目提供支持：当值类型（非类类型）是可选的。如果你在你NSObject子类中声明了如下属性：var myOptionalInt: Int?，我的解决方案将不起作用，因为方法class_copyPropertyList找不到这些属性。
有人有这个问题的解决方案吗？