How can I get key's value from dictionary in Swift?
Use subscripting to access the value for a dictionary key. This will return an Optional:
let apple: String? = companies["AAPL"]
or
if let apple = companies["AAPL"] {
// ...
}
You can also enumerate over all of the keys and values:
var companies = ["AAPL" : "Apple Inc", "GOOG" : "Google Inc", "AMZN" : "Amazon.com, Inc", "FB" : "Facebook Inc"]
for (key, value) in companies {
print("\(key) -> \(value)")
}
Or enumerate over all of the values:
for value in Array(companies.values) {
print("\(value)")
}
From Apple Docs
You can use subscript syntax to retrieve a value from the dictionary for a particular key. Because it is possible to request a key for which no value exists, a dictionary’s subscript returns an optional value of the dictionary’s value type. If the dictionary contains a value for the requested key, the subscript returns an optional value containing the existing value for that key. Otherwise, the subscript returns nil:
https://developer.apple.com/documentation/swift/dictionary
if let airportName = airports["DUB"] {
print("The name of the airport is \(airportName).")
} else {
print("That airport is not in the airports dictionary.")
}
// prints "The name of the airport is Dublin Airport."