ios - 创建 JSON 并格式化 double 值

Question

当我使用 NSJSONSerialization 创建 JSON 时，有什么方法可以设置 double 值的格式吗？

例如:

    let dict :Dictionary<String,NSNumber> = ["key1" : 75.01, "key2" : 80.93, "key3" : 79.07, "key4" : 79.10 ]
    let JSONData = try! NSJSONSerialization.dataWithJSONObject(dict, options: .PrettyPrinted)
    let JSONText = NSString(data: JSONData, encoding: NSASCIIStringEncoding)
    NSLog("JSON string = \(JSONText!)")

我得到以下输出:

JSON string = { "key1" : 75.01000000000001, "key2" : 80.93000000000001, "key4" : 79.09999999999999, "key3" : 79.06999999999999 }

我想避免这些 000001、0999999 等。提前致谢。

Answer 1

使用“Float”代替“NSNumber”:

let dict: Dictionary<String,Float> = ["key1" : 75.01, "key2" : 80.93, "key3" : 79.07, "key4" : 79.10 ]

结果:

JSON string = { "key1" : 75.01, "key4" : 79.1, "key2" : 80.93, "key3" : 79.07 }