Filteredarrayusingpredicate Does Not Exist in Swift Array

filteredArrayUsingPredicate does not exist in swift Array

Swift arrays have a .filter method that takes a closure -- this will do it:

let filteredArray = arrayOfUsers.filter() { $0.userID == "1" }

Closures can be simplified in a variety of ways. The full declaration of the closure would look more like this:

var filteredArray = arrayOfUsers.filter( { (user: UserDetails) -> Bool in
        return user.userID == "1"
    })

The difference between the two is that the first is using trailing closure syntax, shorthand argument names, type inference, and implicit return. You can read more about closures in Apple's Swift documentation.

Swift - Predicate to filter an array by a property of member array

Using string interpolation in predicate format strings is never a good
idea. The correct form of your predicate would be

let searchPredicate = NSPredicate(format: "ANY arr.uid IN %@", ids)

However that checks if any of the uids is in the given list.
To check if all uids are in the given list, the following predicate
should work:

let searchPredicate = NSPredicate(format: "SUBQUERY(arr.uid, $x, $x IN %@).@count = %d", ids, ids.count)

The same can be achieved without predicates in "pure" Swift 3 as

filtered3 = available3.filter { $0.arr.filter { ids.contains($0.uid) }.count == ids.count }

or

filtered3 = available3.filter { Set(ids).isSubset(of: $0.arr.map { $0.uid }) }

How to filter an array using NSPredicate in swift 3

The native Swift equivalent to the ObjC code is

let filteredArray = arrayDirectory.filter { ($0["displayName2"] as! String).range(of: searchText!, options: [.diacriticInsensitive, .caseInsensitive]) != nil }

assuming arrayDirectory is a native Swift Array. It considers also the case insensitive and diacritic insensitive parameters.

NSPredicate to filter an Array of Dictionaries (Swift)

I agree with the comment by @luk2302, in that using the Swift Array filter method is nicer in general than filtering with an NSPredicate. If you're worried about performance across a large data set you should have your content in CoreData and use an NSPredicate as part of an NSFetchRequest with proper indexing setup in your data model.

Having said that, filtering by NSPredicate is not explicitly supporting with the Swift Array type, so you would have to cast to NSArray to use it. It would look something like this:

let filteredArray = (arrayofDictionary as NSArray).filteredArrayUsingPredicate(speciesPredicate)

Problem when an array element i'm trying to filter for does not exist

You can make a pre check before accessing the index for messageIDElement, readStatusElement and filteredMessageID that it not having count 0.

if filteredMessageID.count != 0 {
   if readStatusElement.count != 0 && messageIDElement != 0 {
    // Your code
  }
}

NSPredicate is not working on some object

Really its strange... i unable to find the solution for this. But i found the alternate way to filter the array without using predicate.

tableDataArray = dataSourceArray.filter {$0.firstName.containsString(searchText) || $0.lastName.containsString(searchText) || $0.action.containsString(searchText) }

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