how to check if a property value exists in array of objects in swift

Question

I am trying to check if a specific item (value of a property) exists in a array of objects, but could not find out any solution. Please let me know, what i am missing here.<

Answer 1

This works fine with me:

if(contains(objarray){ x in x.id == 1})
{
     println("1 exists in the array")
}

Answer 2

signature:

let booleanValue = 'propertie' in yourArray;

example:

let yourArray= ['1', '2', '3'];

let contains = '2' in yourArray; => true
let contains = '4' in yourArray; => false

Answer 3

There are mainly 2 viable options here.

1. Use the contains(where: method on objarray. I'm just making a minor modification to @TheEye's answer here:

if objarray.contains(where: { $0.id == 1 }) {
    print("1 exists in the array")
} else {
    print("1 does not exists in the array")
}

2. Override the Equatable protocol conformance requirement and just use contains, like this:

// first conform `Name` to `Equatable`
extension Name: Equatable {
    static func == (lhs: Name, rhs: Name) -> Bool {
        lhs.id == rhs.id
    }
}
// then
let firstName = Name(id: 1, name: "Different Name")
if objarray.contains(firstName) {
    print("1 exists in the array") // prints this out although the names are different, because of the override
} else {
    print("1 does not exists in the array")
}

Answer 4

You can filter the array like this:

let results = objarray.filter { $0.id == 1 }

that will return an array of elements matching the condition specified in the closure - in the above case, it will return an array containing all elements having the id property equal to 1.

Since you need a boolean result, just do a check like:

let exists = results.isEmpty == false

exists will be true if the filtered array has at least one element

Answer 5

A small iteration on @Antonio's solution using the , (where) notation:

if let results = objarray.filter({ $0.id == 1 }), results.count > 0 {
   print("1 exists in the array")
} else {
   print("1 does not exists in the array")
}

Answer 6

In Swift 3:

if objarray.contains(where: { name in name.id == 1 }) {
    print("1 exists in the array")
} else {
    print("1 does not exists in the array")
}