Ios 快速语法';箱子出租';in-for循环令人困惑
如果目标是让'result'在'results'数组中表示一个对象,为什么不在下面的Ios 快速语法';箱子出租';in-for循环令人困惑,ios,swift,syntax,Ios,Swift,Syntax,如果目标是让'result'在'results'数组中表示一个对象,为什么不在下面的case let中删除,而只使用'for result in'?我不明白为什么这里需要case let if let data = data, let json = try? JSONSerialization.jsonObject(with: data, options: []) as? [String: Any] { for case let result in json["results"] {
case let
中删除,而只使用'for result in'?我不明白为什么这里需要case let
if let data = data, let json = try? JSONSerialization.jsonObject(with: data, options: []) as? [String: Any] {
for case let result in json["results"] {
if let restaurant = Restaurant(json: result) {
restaurants.append(restaurant)
}
}
}
JSON
{
"query": "sandwich",
"results_count": 12,
"page": 1,
"results": [
{
"name": "Caffè Macs",
"coordinates": {
"lat": 37.330576,
"lng": -122.029739
},
"meals": ["breakfast", "lunch", "dinner"]
},
...
]
}
REF:在您的情况下,不需要将
case let
与for循环一起使用,因为您需要结果
响应的所有对象,如果您想了解case let
是如何使用的,请检查此项
let albumDic = [
("Red", 2014),
("1989", 2014),
("Fearless", 2008),
("Speak Now", 2008)
]
for case let (album, 2014) in albumDic {
print("Album \(album) was released in 2014")
}
输出
Album Red was released in 2014
Album 1989 was released in 2014
注意:您可以直接使用for in-loop,无需使用case let
,因为您需要所有对象,所以需要这样编写
if let results = json["results"] as? [[String: Any]]{
for result in results {
}
}
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