ios - 如何检查数组中是否有重复值？

Question

var arrEmails = NSMutableArray()
arrEmails = ["a.a@gmail.com", "a.a1@gmail.com", "a.a@gmail.com", "b.b@gmail.com", "c.c@gmail.com", "a.a1@gmail.com"]

上面是我的数组，我想检查是否有重复值。为此，我写了下面的代码。

let set = NSCountedSet.init(array: arrEmails as! [Any])
        var duplicates: Int = 0

        for var object in set {
            if set.count(for: object) > 1 {
                duplicates = duplicates+1
            }
        }

但在上面的代码中，如果数组包含如下值，它会返回重复值 1。

arrEmails = ["a.a@gmail.com", "", "", "b.b@gmail.com", "", ""]

我不想删除重复值，我只想检查数组中重复值的数量。怎么查？请帮助我。

Answer 1

First of all stop using NSMutableArray and use Swift array.

所以你有这个数组

let emails = ["a.a@gmail.com", "a.a1@gmail.com", "a.a@gmail.com", "b.b@gmail.com", "c.c@gmail.com", "a.a1@gmail.com"]

现在你可以简单的写检查是否有重复

let hasDuplicates = emails.count != Set(emails).count

Note, this does work only if the generic type of the array is Hashable.