提取值从__NSArrayM

Question

我已经印刷，我想是这样的值：

a = Optional(<__NSArrayM 0x1704494b0>(9)) 

我如何提取价值9？ 我写了这一点，但错误的是：let a = (parseJSON[index] as AnyObject).object(forKey: "subjects_count")

Answer 1

试试这个： -

guard let a = (parseJSON[index] as AnyObject).object(forKey: "subjects_count"), let value = a.first else {return} 
let stringValue = String(value) 
print(stringValue) 

Answer 2

使用SWIFT原生类型和主键/索引订阅

if let dict = parseJSON[index] as? [String:Any], 
    let subjectsCount = dict["subjects_count"] as? [Int], !subjectsCount.isEmpty { 
    print(subjectsCount[0]) 
}