如何比较两个数组对象-Swift 4

Question

I have 2 Array of type [Any] - objects of dictionaries
And other array contains other set of objects [Any] (2nd array objects are contains in first array)

I need to find the index of the first array of second array elements

eg: -

let firstArray = [["key1":6],["key2":8],["key3":64],["key4":68],["key5":26],["key6":76]]

let secondArray = [["key3":64],["key6":68]]

How can I find the firstArray index of secondArray elements

Answer 1

let index = firstArray.index{$0 == secondArray[0]};
print("this value ", index);

will print optional(2) , it is basically 2

Answer 2

First, you take the keys from your secondArray . Then, you try to find the index of key in your firstArray . Be aware that some values might be nil if the key doesn't exist.

let firstArray = [["key1":6],["key2":8],["key3":64],["key4":68],["key5":26],["key6":76]]
let secondArray = [["key3":64],["key6":68], ["key8": 100]]

let indexes = secondArray
    .map({ $0.first?.key }) //map the values to the keys
    .map({ secondKey -> Int? in
        return firstArray.index(where:
            { $0.first?.key == secondKey } //compare the key from your secondArray to the ones in firstArray
        )
    })

print(indexes) //[Optional(2), Optional(5), nil]

I also added an example case where the result is nil.