我正在嘗試使用 Swift 構建以下 JSON，因為這在我使用 Postman 進行測驗時有效。我需要能夠更改引數的值，所以我試圖避免只構建一個字串：
{
"item": {
"record": "10",
"field_name": "orientation_forward",
"redcap_repeat_instance": "1",
"redcap_repeat_instrument": "range_of_motion_result",
"value": "4",
"redcap_event_name": []
}
}
這是我這樣做的嘗試，但當我測驗它時，它甚至似乎不是有效的 JSON：
var record = "10"
var field_name = "orientation_forward"
var repeat_instance = "1"
var repeat_instrument = "range_of_motion_result"
var value = "4"
var event: [String] = [] // not sure how else to pass in '[]' when empty
let dataObject: [String: Any] = [
"item":
["record": record,
"field_name": field_name,
"redcap_repeat_instance": repeat_instance,
"redcap_repeat_instrument": repeat_instrument,
"value": value,
"redcap_event_name": event]
]
if let jsonData = try? JSONSerialization.data(withJSONObject: dataObject, options: .init(rawValue: 0)) as? Data
{
// Check if it worked...
print(String(data: jsonData!, encoding: .utf8)!)
let jsonTest = JSONSerialization.isValidJSONObject(jsonData) // false!
print(jsonTest)
}
所有的幫助都親切地接受了。提前致謝。
uj5u.com熱心網友回復：
最好的方法是在Codable這里使用，開始做更多的作業，但最終的代碼更干凈。
所以首先我們創建一個結構，它符合 Codable
struct Item: Codable {
let record: String
let fieldName: String
let repeatInstance: String
let repeatInstrument: String
let value: String
let event: [String]
enum CodingKeys: String, CodingKey {
case record
case fieldName = "field_name"
case repeatInstance = "redcap_repeat_instance"
case repeatInstrument = "redcap_repeat_instrument"
case value
case event = "redcap_event_name"
}
}
CodingKeys列舉用于獲取正確的欄位名稱
然后像這樣使用
let item = Item(record: "10", fieldName: "orientation_forward", repeatInstance: "1", repeatInstrument: "range_of_motion_result", value: "4", event: [])
do {
let data = try JSONEncoder().encode(["item": item])
if let s = String(data: data, encoding: .utf8) { print(s) }
} catch {
print(error)
}
{"item":{"field_name":"orientation_forward","value":"4","re??dcap_event_name":[],"redcap_repeat_instrument":"range_of_motion_result","re??cord":"10","re??dcap_repeat_instance":" 1"}}
有些人更喜歡一直使用自定義型別，如果是這樣，您可以創建頂級結構而不是使用字典
struct ItemContainer: Codable {
let item: Item
}
然后編碼會變成類似
let data = try JSONEncoder().encode(ItemContainer(item: item))
但最終結果是一樣的
轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/418738.html
標籤：