Removeobjectsatindexes For Swift Arrays

Remove objects at specific indexes from Array in Swift 5

What you can do:

• Get all indices
• Sort them descending
• Iterate over the indices, and remove the item at that index

Why reversed? Because else, imagine you have the indices [0, 1], and your array is [A, B, C]
If you start looping on the indices, you'll have :
0: Remove first from [A, B, C] -> [B, C]
1: Remove second from [B, C] -> [B]

So, if you are using Swift Array:

let indices = listToBeRemoved.map{ $0.row }.sorted()
indices.reversed().forEach{ listArray.remove(at: $0) }

Since you are using NSMutableArray (I'd strongly recommend you to avoir NSStuff when Stuff is available): listArray.remove(at: $0) is listArray.removeObject(at: $0)

Another possible solution:

let indices = IndexSet(listToBeRemoved.map{ $0.row })
listArray.removeObjects(at: indices) //Objective-C
listArray.remove(attOffsets: indices) //Swift

Swift remove objects in Array range

Use removeSubrange method of array. Make a valid range by element location and length.

var array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
let range = 1...3
array.removeSubrange(range)

print(array)

Output: [1, 5, 6, 7, 8, 9, 10]

Note: Range should be a valid range I mean it should not be out from array.

Here is yours way (by for loop)
We can not remove objects by their indexes in a loop because every time object removes array's count and objects indexes will be change so out of range crash can come or you might get a wrong output. So you will have to take help of another array. See below example:-

var array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
var newArray: [Int] = []
let minRange = 1
let maxRange = 3
for i in 0..<array.count {
     if i >= minRange && i <= maxRange {
        /// Avoid
        continue
     }

     newArray.append(array[i])
}

print(newArray)

Output: [1, 5, 6, 7, 8, 9, 10]

Swift 3 Array, remove more than one item at once, with .remove(at: i)

It's possible if the indexes are continuous using removeSubrange method.
For example, if you would like to remove items at index 3 to 5:

myArray.removeSubrange(ClosedRange(uncheckedBounds: (lower: 3, upper: 5)))

For non-continuous indexes, I would recommend remove items with larger index to smaller one. There is no benefit I could think of of removing items "at the same time" in one-liner except the code could be shorter. You can do so with an extension method:

extension Array {
  mutating func remove(at indexes: [Int]) {
    for index in indexes.sorted(by: >) {
      remove(at: index)
    }
  }
}

Then:

myArray.remove(at: [3, 5, 8, 12])

UPDATE: using the solution above, you would need to ensure the indexes array does not contain duplicated indexes. Or you can avoid the duplicates as below:

extension Array {
    mutating func remove(at indexes: [Int]) {
        var lastIndex: Int? = nil
        for index in indexes.sorted(by: >) {
            guard lastIndex != index else {
                continue
            }
            remove(at: index)
            lastIndex = index
        }
    }
}


var myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
myArray.remove(at: [5, 3, 5, 12]) // duplicated index 5
// result: [0, 1, 2, 4, 6, 7, 8, 9, 10, 11, 13] only 3 elements are removed

Swift: Excluding a specific index from an array when filtering

You can use enumerated() to convert a sequence(eg. Arrays) to a sequence of tuples with an integer counter and element paired together

var a = [1,2,3,4,5,6,7]
var c = 1
let value  = a.enumerated().reduce(1) { (_, arg1) -> Int in
    let (index, element) = arg1
    c = index != 2 ? c*element : c
    return c
}
print(value) // prints 1680 i.e. excluding index 2

array removeObjectsAtIndexes:

use syntax like this for crash free delete;

NSArray *array = [NSArray arrayWithArray: _targets];

for(CCSprite *sprite in array)
{
    if(sprite.tag == kToDelete) //mark somewhere in game :or use ur logic here
    {
        [_targets removeObject: sprite];
        [sprite stopAllActions];
        [sprite removeFromParentAndCleanup:YES];
    }
}

How convert [Int] to int?

index is array of Int. But you need to pass Int to the remove method.

If you want to remove all objects for selected row indexes, than write:

let indexes = tableView.selectedRowIndexes.map { Int($0) }
indexes.reversed().forEach { arrDomains.remove(at: $0) }

If you want to remove object at some index, than write:

guard let index = tableView.selectedRowIndexes.map { Int($0) }.first(where: { /*.your condition here */ }) else { return }
arrDomains.remove(at: $0)

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