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iOS Swift Basics (retired) Collections What is a Dictionary?

Posted by swiftfun
swiftfun
4,039 Points

Why this does not work?

With a dictionary, the following optional works:

let todo = ["Return Calls":"Pez"]
if let todoThing = todo["Return Calls"] {
    println("Tu lista si contiene la tarea de \(todoThing)")
} else {
    println("Tu lista no contiene ese elemento")
}

Whereas when using an array, it does not work:

let todo = ["Return Calls"]
if let todoThing = todo["Return Calls"] {
    println("Tu lista si contiene la tarea de \(todoThing)")
} else {
    println("Tu lista no contiene ese elemento")
}

WHY? Please help

Ryan Duchene
Ryan Duchene
Courses Plus Student 46,022 Points

Added syntax highlighting to your posts. :)

1 Answer

Arman Kussainov
Arman Kussainov
4,754 Points
Arman Kussainov
Arman Kussainov
4,754 Points

Because when using array you can't do like this todo["Return Calls"] . You can get value of array's elements like todo[0], todo[1] and etc.

swiftfun
swiftfun
4,039 Points

It doesn't work either. It seems this is not the correct way to use an if statement with an array.

let todo = ["Return Calls"]
if let todoThing = todo[0] {
    println("Tu lista si contiene la tarea de \(todoThing)")
} else {
    println("Tu lista no contiene ese elemento")
}