我有两个字典作为[String: Any]类型的文本属性工作，为了切换所需属性的ON或OFF，我需要检查两个字典是否相同。
我尝试了以下内容：
let current = inputTextView.typingAttributes
let undo = current.elementsEqual(attributes, by: { (arg0, arg1) -> Bool in
return ((arg0.key == arg1.key) && (arg0.value == arg1.value))
})
但是在第二次评估中我得到了错误：
二元运算符'=='不能应用于两个'任意'操作数
比较两个类型为[String: Any]的
谢谢
答案 0 :(得分：2)
Any不符合Equatable协议。如果使用==运算符，它是类型必须的。因此，您需要使用this answer中提到的带有类型参数的函数来比较Any个对象：
func isEqual<T: Equatable>(type: T.Type, a: Any, b: Any) -> Bool? {
guard let a = a as? T, let b = b as? T else { return nil }
return a == b
}
但是，要使用此功能，您应该知道typingAttributes中每个值的确切类型。您可以使用Mirror结构实现此目的，如下所示：
let lilAny: Any = "What's my type? :("
print(Mirror(reflecting: lilAny).subjectType) // String
答案 1 :(得分：0)
import Foundation
func areEqual (_ left: Any, _ right: Any) -> Bool {
if type(of: left) == type(of: right) &&
String(describing: left) == String(describing: right) { return true }
if let left = left as? [Any], let right = right as? [Any] { return left == right }
if let left = left as? [AnyHashable: Any], let right = right as? [AnyHashable: Any] { return left == right }
return false
}
extension Array where Element: Any {
static func == (left: [Element], right: [Element]) -> Bool {
if left.count != right.count { return false }
for (index, leftValue) in left.enumerated() {
guard areEqual(leftValue, right[index]) else { return false }
}
return true
}
static func != (left: [Element], right: [Element]) -> Bool {
return !(left == right)
}
}
extension Dictionary where Value: Any {
static func == (left: [Key : Value], right: [Key : Value]) -> Bool {
if left.count != right.count { return false }
for element in left {
guard let rightValue = right[element.key],
areEqual(rightValue, element.value) else { return false }
}
return true
}
static func != (left: [Key : Value], right: [Key : Value]) -> Bool {
return !(left == right)
}
}
let comparisonResult = ["key1": 1, 2: "Value2"] == ["key1": ["key2":2]] // false
print("!!!! \(comparisonResult)")
func test(dict1: [AnyHashable : Any], dict2: [AnyHashable : Any]) {
print("========================")
print("dict1: \(dict1)")
print("dict2: \(dict2)")
print("are\(dict1 == dict2 ? " " : " not ")equal")
}
test(dict1: ["key1": 1, 2: "Value2"],
dict2: ["key1": 1, 2: "Value2"])
test(dict1: ["key1": 1, 2: "Value2"],
dict2: ["key1": 1])
test(dict1: [2: "Value2"],
dict2: ["key1": 1])
test(dict1: ["1": 1],
dict2: [1: 1])
test(dict1: [1: 2],
dict2: [1: 3])
test(dict1: ["key1": [1,2,3,4]],
dict2: ["key1": [1,2,3,4]])
test(dict1: ["key1": [1,2,3,4]],
dict2: ["key1": [1,2,3,"4"]])
test(dict1: ["key1": ["key2":2]],
dict2: ["key1": ["key2":2]])
test(dict1: ["key1": ["key2":2]],
dict2: ["key1": ["key2":3]])
test(dict1: ["key1": ["key2":2]],
dict2: ["key1": ["key2":3]])
test(dict1: ["key1": [1,2,3,4] as [Any]],
dict2: ["key1": [1,2,3,4] as [Int]])
test(dict1: ["key1":[1: "key1"] as [AnyHashable: Any]],
dict2: ["key1":[1: "key1"] as [AnyHashable: String]])
test(dict1: ["key1":[1: "key1"] as [AnyHashable: Any]],
dict2: ["key1":[2: "key1"] as [AnyHashable: String]])
========================
dict1: [AnyHashable("key1"): 1, AnyHashable(2): "Value2"]
dict2: [AnyHashable("key1"): 1, AnyHashable(2): "Value2"]
are equal
========================
dict1: [AnyHashable("key1"): 1, AnyHashable(2): "Value2"]
dict2: [AnyHashable("key1"): 1]
are not equal
========================
dict1: [AnyHashable(2): "Value2"]
dict2: [AnyHashable("key1"): 1]
are not equal
========================
dict1: [AnyHashable("1"): 1]
dict2: [AnyHashable(1): 1]
are not equal
========================
dict1: [AnyHashable(1): 2]
dict2: [AnyHashable(1): 3]
are not equal
========================
dict1: [AnyHashable("key1"): [1, 2, 3, 4]]
dict2: [AnyHashable("key1"): [1, 2, 3, 4]]
are equal
========================
dict1: [AnyHashable("key1"): [1, 2, 3, 4]]
dict2: [AnyHashable("key1"): [1, 2, 3, "4"]]
are not equal
========================
dict1: [AnyHashable("key1"): ["key2": 2]]
dict2: [AnyHashable("key1"): ["key2": 2]]
are equal
========================
dict1: [AnyHashable("key1"): ["key2": 2]]
dict2: [AnyHashable("key1"): ["key2": 3]]
are not equal
========================
dict1: [AnyHashable("key1"): ["key2": 2]]
dict2: [AnyHashable("key1"): ["key2": 3]]
are not equal
========================
dict1: [AnyHashable("key1"): [1, 2, 3, 4]]
dict2: [AnyHashable("key1"): [1, 2, 3, 4]]
are equal
========================
dict1: [AnyHashable("key1"): [AnyHashable(1): "key1"]]
dict2: [AnyHashable("key1"): [AnyHashable(1): "key1"]]
are equal
========================
dict1: [AnyHashable("key1"): [AnyHashable(1): "key1"]]
dict2: [AnyHashable("key1"): [AnyHashable(2): "key1"]]
are not equal