CODEWITHSUNDEEP
swiftdictionaryiteration
Anuj Arora
Anuj Arora

Reputation: 3057

Swift Dictionary Multiple Key Value Pairs - Iteration

In Swift I want to make an array of dictionaries (with multiple key value pairs) and then iterate over each element

Below is the expected output of a possible dictionary. Not sure how to declare and intitialize it (somewhat similar to array of hashes in Ruby)

 dictionary = [{id: 1, name: "Apple", category: "Fruit"}, {id: 2, name: "Bee", category: "Insect"}]

I know how to make an array of dictionary with one key value pair. For example:

 var airports: [String: String] = ["YYZ": "Toronto Pearson", "DUB": "Dublin"]

Upvotes: 4

Views: 10364

Answers (3)

Duyen-Hoa
Duyen-Hoa

Reputation: 15804

to declare an array of dictionary, use this:

var arrayOfDictionary: [[String : AnyObject]]  = [["id" :1, "name": "Apple", "category" : "Fruit"],["id" :2, "name": "Microsoft", "category" : "Juice"]]

I see that in your dictionary, you mix number with string, so it's better use AnyObject instead of String for data type in dictionary. If after this code, you do not have to modify the content of this array, declare it as 'let', otherwise, use 'var'

Update: to initialize within a loop:

//create empty array
var emptyArrayOfDictionary = [[String : AnyObject]]()
for x in 2...3 {  //... mean the loop includes last value => x = 2,3
    //add new dictionary for each loop
    emptyArrayOfDictionary.append(["number" : x , "square" : x*x ])
}
//your new array must contain: [["number": 2, "square": 4], ["number": 3, "square": 9]]

Upvotes: 5

Arsen
Arsen

Reputation: 10961

let airports: [[String: String]] = [["YYZ": "Toronto Pearson", "DUB": "Dublin"]]

for airport in airports {
    print(airport["YYZ"])
}

Upvotes: 1

Michael Dorner
Michael Dorner

Reputation: 20205

let dic_1: [String: Int] = ["one": 1, "two": 2]
let dic_2: [String: Int] = ["a": 1, "b": 2]
let list_1 = [dic_1, dic_2]

// or in one step:
let list_2: [[String: Int]] = [["one": 1, "two": 2], ["a": 1, "b": 2]]

for d in list_1 { // or list_2
    print(d)
}

which results in

["one": 1, "two": 2]

["b": 2, "a": 1]

Upvotes: 1

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