NSJSONSerialization成swift词典

时间:2015-04-19 11:22:19

标签: json swift nsdictionary swift-dictionary

我有一个json对象,我需要序列化到字典中。我知道我可以将它序列化为NSDictionary但是从

开始

“在Swift 1.2中,具有原生Swift等价物的Objective-C类(NSString,NSArray,NSDictionary等)不再自动桥接。”

参考:[http://www.raywenderlich.com/95181/whats-new-in-swift-1-2]

我宁愿在原生的swift词典中使用它来避免尴尬的桥接。

我无法使用NSJSONSerialization方法,因为它只映射到NSDictionay。将JSON序列化为快速字典的另一种方法是什么?

1 个答案:

答案 0 :(得分:4)

您可以直接使用Swift词典NSJSONSerialization

{"id": 42}的示例:

let str = "{\"id\": 42}"
let data = str.dataUsingEncoding(NSUTF8StringEncoding)

let json = NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers, error: nil) as! [String:Int]

println(json["id"]!)  // prints 42

AnyObject

let json = NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers, error: nil) as! [String:AnyObject]

if let number = json["id"] as? Int {
    println(number)  // prints 42
}

Playground screenshot

<强>更新

如果您的数据可能为零,则必须使用安全展开以避免错误:

let str = "{\"id\": 42}"
if let data = str.dataUsingEncoding(NSUTF8StringEncoding) {
    // With value as Int
    if let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as? [String:Int] {
        if let id = json["id"] {
            println(id)  // prints 42
        }
    }
    // With value as AnyObject
    if let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as? [String:AnyObject] {
        if let number = json["id"] as? Int {
            println(number)  // prints 42
        }
    }
}

Swift 2.0更新

do {
    let str = "{\"id\": 42}"
    if let data = str.dataUsingEncoding(NSUTF8StringEncoding) {
        // With value as Int
        if let json = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? [String:Int] {
            if let id = json["id"] {
                print(id)  // prints 42
            }
        }
        // With value as AnyObject
        if let json = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? [String:AnyObject] {
            if let number = json["id"] as? Int {
                print(number)  // prints 42
            }
        }
    }
} catch {
    print(error)
}