parsing array in array into some arrays in swift 4? - ios

Question

I used parsing son in my codes for news api
the son is some thing like this
> {
"status": "ok",
"source": "associated-press",
"sortBy": "top",
-"articles": [
-{
"author": "CHRISTINA A. CASSIDY and MEGHAN HOYER",
"title": "Pro-Trump states most affected by his health care decision",
"description": "President Donald Trump's decision to end a provision of the Affordable Care Act that was benefiting roughly 6 million Americans helps fulfill a campaign promise",
"url": "https:urlexample",
"urlToImage": "url example",
},
-{
"author": "CHRISTINA A. CASSIDY and MEGHAN HOYER",
"title": "Pro-Trump states most affected by his health care decision",
"description": "President Donald Trump's decision to end a provision of the Affordable Care Act that was benefiting roughly 6 million Americans helps fulfill a campaign promise",
"url": "https:urlexample",
"urlToImage": "url example",
},
]
}
as you see in each array we have title - description and more
I want to parse this jason into separated array for example append all of the titles in one array and append all of the descriptions in another ones and more
here is my code
struct Response : Decodable {
let articles: articles
}
struct articles: Decodable {
let title: String
let description : String
let url : String
let urlToImage : String
}
and here is the codes for json
let jsonUrl = "https://newsapi.org/[your codes]"
guard let url = URL(string : jsonUrl) else {
return
}
URLSession.shared.dataTask(with: url) { (data , response , error) in
guard let data = data else {return}
do {
let article = try JSONDecoder().decode(Response.self , from : data)
print(article.articles.title)
print(article.articles.description)
print(article.articles.url)
print(article.articles.urlToImage)
}
catch {
print(error)
}
}.resume()
and when I run this I will receive this error
"Expected to decode Dictionary but found an array instead.", underlyingError: nil))

Answer 1

First, to distinguish between property/method names and type names, try to follow Swift naming conventions: (the following is from Swift API Design guidelines)
Names of types and protocols are UpperCamelCase. Everything else is lowerCamelCase.
Also, your articles struct represents data for just one article, not multiple. So it should start with a capital A, and be singular:
struct Article: Decodable {
Secondly, if you take another look at the JSON you're getting back, articles is an array of dictionaries:
-"articles": [
-{
"author": "CHRISTINA A. CASSIDY and MEGHAN HOYER",
...
},
-{
"author": "CHRISTINA A. CASSIDY and MEGHAN HOYER",
...
},
So the articles property in your Response struct should be an array of Article.
struct Response : Decodable {
let articles: [Article]
}