将JSON转换为自定义对象时出错 [英] Error casting JSON to custom object

问题描述

我对我来说有一个晦涩的错误.

I have an obscure error for me.

我尝试使用Custom Oject反序列化字典.但这不起作用.

I try to deserialize a Dictionary with Custom Oject. But it doesn't work.

let decodedJson = try! NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.AllowFragments) as! Dictionary<String, TestCast>

我的对象是(我已经测试了Objective-c对象，但结果相同)

My object is (I have test with objective-c object but I have a same result)

class TestCast: NSObject {

    var ca:String?
    var resultat:String?
    var remuneration:String?
    var delta_ca:String?
    var delta_resultat:String?
    var delta_remuneration:String?

}

我的json是:

{
"201310": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201311": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201312": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201401": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201402": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201403": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201404": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201405": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201406": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201407": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201408": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201409": {
    "resultat": 0,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 0,
    "remuneration": 0,
    "delta_ca": "0.00"
},
"201410": {
    "resultat": 3938.33,
    "delta_resultat": "3,938.33",
    "delta_remuneration": "-2,700.00",
    "ca": 3938.33,
    "remuneration": 2700,
    "delta_ca": "3,938.33"
},
"201411": {
    "resultat": 3938.33,
    "delta_resultat": "0.00",
    "delta_remuneration": "0.00",
    "ca": 3938.33,
    "remuneration": 2700,
    "delta_ca": "0.00"
},
"201412": {
    "resultat": 34211.1,
    "delta_resultat": "30,272.77",
    "delta_remuneration": "0.00",
    "ca": 34211.1,
    "remuneration": 2700,
    "delta_ca": "30,272.77"
},
"201501": {
    "resultat": 7812.89,
    "delta_resultat": "-26,398.21",
    "delta_remuneration": "2,700.00",
    "ca": 13500,
    "remuneration": 0,
    "delta_ca": "-20,711.10"
},
"201502": {
    "resultat": -20195.54,
    "delta_resultat": "-28,008.43",
    "delta_remuneration": "0.00",
    "ca": 5700,
    "remuneration": 0,
    "delta_ca": "-7,800.00"
},
"201503": {
    "resultat": 2379.71,
    "delta_resultat": "22,575.25",
    "delta_remuneration": "0.00",
    "ca": 4650,
    "remuneration": 0,
    "delta_ca": "-1,050.00"
},
"201504": {
    "resultat": 14582.38,
    "delta_resultat": "12,202.67",
    "delta_remuneration": "0.00",
    "ca": 16500,
    "remuneration": 0,
    "delta_ca": "11,850.00"
},
"201505": {
    "resultat": 4568.45,
    "delta_resultat": "-10,013.93",
    "delta_remuneration": "0.00",
    "ca": 9200,
    "remuneration": 0,
    "delta_ca": "-7,300.00"
},
"201506": {
    "resultat": 9941.67,
    "delta_resultat": "5,373.22",
    "delta_remuneration": "-49.60",
    "ca": 12349.67,
    "remuneration": 49.6,
    "delta_ca": "3,149.67"
},
"201507": {
    "resultat": 8138.53,
    "delta_resultat": "-1,803.14",
    "delta_remuneration": "-90.40",
    "ca": 13526.67,
    "remuneration": 140,
    "delta_ca": "1,177.00"
},
"201508": {
    "resultat": 3321.47,
    "delta_resultat": "-4,817.06",
    "delta_remuneration": "140.00",
    "ca": 4500,
    "remuneration": 0,
    "delta_ca": "-9,026.67"
},
"201509": {
    "resultat": -2454.47,
    "delta_resultat": "-5,775.94",
    "delta_remuneration": "-23.00",
    "ca": 0,
    "remuneration": 23,
    "delta_ca": "-4,500.00"
}}

我有一个错误:

无法将类型'__NSCFDictionary'(0x104f04ef0)的值强制转换为'Pulse.TestCast'

Could not cast value of type '__NSCFDictionary' (0x104f04ef0) to 'Pulse.TestCast'

推荐答案

将字典数组类型转换为类不会自动使用字典数据创建此类的实例...

Typecasting an array of dictionaries to a class doesn't automagically create instances of this class with the dictionaries data...

您必须为您的类创建一个初始化程序，该初始化程序将来自JSON的字典作为参数来初始化具有正确类型的值.

You have to create an initializer for your class that takes a dictionary from your JSON as a parameter to init the values with the right types.

示例:

class TestCast: NSObject {
    var ca:Int?
    var resultat:Double?
    var remuneration:Int?
    var delta_ca:String?
    var delta_resultat:String?
    var delta_remuneration:String?
    init(dictionary: [String:AnyObject]) {
        self.ca = dictionary["ca"] as? Int
        self.resultat = dictionary["resultat"] as? Double
        self.delta_resultat = dictionary["delta_resultat"] as? String
        self.delta_ca = dictionary["delta_ca"] as? String
        self.remuneration = dictionary["remuneration"] as? Int
        self.delta_remuneration = dictionary["delta_remuneration"] as? String
    }
}

do {
    if let unwrappedData = data, let json = try NSJSONSerialization.JSONObjectWithData(unwrappedData, options: []) as? [String:[String:AnyObject]] {
        let casts = json.map { TestCast(dictionary: $1) }
        // here `casts` is an array of TestCast objects
    }
} catch let error as NSError {
    print(error.description)
}

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