最近在学习swift,也是按照别人的代码敲打的水平,虽然时间不长,但是还是深刻的感觉到swift结构体和枚举的强大,下面是本人从别人代码里看到的一段关于json解析的封装,感觉非常不错所以想和大家分享分享,也借此来记录我学习的脚步。
在没有看到这段代码之前,我是用一个简单的方法进行解析,数据返回的形式是Any,我是强制性转化为AnyObject返回给调用者
let object: Any = try JSONSerialization.jsonObject(with: data, options: opt)
没有对数据类型进行任何判断,因为一般数据解析,我们都是可以提前看到数据类型的,也没有必要在这进行太多的判断,我是这样侥幸的想的。
偶尔看到了这段代码,所以也想和大家分享一下
1.定义了一个枚举类表示数据类型
public enum Type :Int{
case number
case string
case bool
case array
case dictionary
case null
case unknown
}
2.然后定义了一个JSON结构体来做这件事
public struct JSON {
public init(data:Data, options opt: JSONSerialization.ReadingOptions = .allowFragments, error: NSErrorPointer? = nil) {
do {
let object: Any = try JSONSerialization.jsonObject(with: data, options: opt)
self.init(object as AnyObject)
} catch let aError as NSError {
if error != nil {
error??.pointee = aError
}
self.init(NSNull())
}
}
public init(_ object: AnyObject) {
self.object = object
}
/// Private object
fileprivate var rawArray: [AnyObject] = []
fileprivate var rawDictionary: [String : AnyObject] = [:]
fileprivate var rawString: String = ""
fileprivate var rawNumber: NSNumber = 0
fileprivate var rawNull: NSNull = NSNull()
fileprivate var _type: Type = .null
fileprivate var _error: NSError? = nil
var object : AnyObject{
get
{
switch self._type {
case .array:
return self.rawArray as AnyObject
case .dictionary:
return self.rawDictionary as AnyObject
case .string:
return self.rawString as AnyObject
case .number:
return self.rawNumber as AnyObject
case .bool:
return self.rawNumber as AnyObject
default:
return self.rawNull
}
}set{
_error = nil
switch newValue {
case let number as NSNumber:
if number.boolValue {
_type = .bool
}else{
_type = .number
}
self.rawNumber = number
case let string as String:
_type = .string
self.rawString = string
case _ as NSNull:
_type = .null
case let array as [AnyObject]:
_type = .array
self.rawArray = array
case let dictionary as [String : AnyObject]:
_type = .dictionary
self.rawDictionary = dictionary
default:
_type = .unknown
_error = NSError.init(domain: "SwiftyJSONErrorDomain", code: 999, userInfo: [NSLocalizedDescriptionKey: "It is a unsupported type"])
}
}
}
}
整段代码对数据类型判断的很全面,虽然代码量有点多,但是找不到方法去拒绝。