How to remove single object in array from multiple matching object

Question

var testarray = NSArray() 
testarray = [1,2,2,3,4,5,3] 
print(testarray) 
testarray.removeObject(2)

I want to remove single object from multiple matchi

Answer 1

Swift 2

Solution when using a simple Swift array:

var myArray = [1, 2, 2, 3, 4, 3]

if let index = myArray.indexOf(2) {
    myArray.removeAtIndex(index)
}

It works because .indexOf only returns the first occurence of the found object, as an Optional (it will be nil if object not found).

It works a bit differently if you're using NSMutableArray:

let nsarr = NSMutableArray(array: [1, 2, 2, 3, 4, 3])
let index = nsarr.indexOfObject(2)
if index < Int.max {
    nsarr.removeObjectAtIndex(index)
}

Here .indexOfObject will return Int.max when failing to find an object at this index, so we check for this specific error before removing the object.

Swift 3

The syntax has changed but the idea is the same.

Array:

var myArray = [1, 2, 2, 3, 4, 3]
if let index = myArray.index(of: 2) {
    myArray.remove(at: index)
}
myArray // [1, 2, 3, 4, 3]

NSMutableArray:

let myArray = NSMutableArray(array: [1, 2, 2, 3, 4, 3])
let index = myArray.index(of: 2)
if index < Int.max {
    myArray.removeObject(at: index)
}
myArray // [1, 2, 3, 4, 3]

In Swift 3 we call index(of:) on both Array and NSMutableArray, but they still behave differently for different collection types, like indexOf and indexOfObject did in Swift 2.

Answer 2

If you want to remove all duplicate objects then you can use below code.

    var testarray = NSArray()
    testarray = [1,2,2,3,4,5,3]

    let set = NSSet(array: testarray as [AnyObject])
    print(set.allObjects)