Check element in array with different objects

Question

I have an array with custom objects by 2 types. Also I have TableView, which shows objects from array. I need to select tableViewCell and check, if the element already in array - remove it from array, otherwise add it to array. I know, there is method for the checking array.contains(element) but my array looks like [Any] and it doesn't have this method.

I'm trying to check it with use for-in, but it's not good solution.

How can I do this?

let a: Int = 5
let b: String = "3"
let array: [Any] = [a, b]

check solution there https://stackoverflow.com/questions/34778950/how-to-compare-any-value-types — Abdelahad Darwish, May 04 '18 at 06:39

Vlad Khambir · Accepted Answer · 2018-05-04T07:04:20.597

2

You are able to cast Any to Int or String type and just use array.contains

array.contains {
    if let intValue = $0 as? Int {
        return intValue == 3
    } else if let stringValue = $0 as? String {
        return stringValue == "3"
    }
    return false
}

OR use this extension (Swift 4):

extension Array where Element: Any {
    func contains<T: Equatable>(_ element: T) -> Bool {
        return contains {
            guard let value = $0 as? T else { return false }
            return value == element
        }
    }
}


array.contains("3") // true for your example

edited May 04 '18 at 07:04

answered May 04 '18 at 06:36

Vlad Khambir

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in example only 2 base classes, but in my code this is 4 or more custom classes – Sergey Hleb May 04 '18 at 06:40
@SergeyHleb I have just added extension for array, use this extension for any your custom type. – Vlad Khambir May 04 '18 at 06:41
let me few minutes, I check this – Sergey Hleb May 04 '18 at 06:42
I'm trying your suggestion, but there is `Use of unresolved identifier 'array'`. I doing something stupid thing like: `(_ element: T, array: [Any])`, and in call it looks like: `addingDevices.contains(device, array: addingDevices)`, but it works perfect, thank you. – Sergey Hleb May 04 '18 at 06:57
I understood it, okay. – Sergey Hleb May 04 '18 at 07:03
2

Replace `array.contains` with `self.contains` in `extension`. Otherwise no benefit in making of `extension`. – TheTiger May 04 '18 at 07:03
I already doing this, thank you. But I have one more question, if element already in array, how can I remove it? I don't know it's position – Sergey Hleb May 04 '18 at 07:06
@TheTiger thank you, I've missed this. We are able to use just `contains` without `self`, so I have just fixed this. – Vlad Khambir May 04 '18 at 07:07

Check element in array with different objects

1 Answers1