Swift:
let insetIndex = 3 // your any insert index
var array1 = ["1", "2", "3", "4", "5"]
let array2 = ["10", "11"]
array1.insert(contentsOf: array2, at: insetIndex)
OC:
int loc = 3; // your any insert index
NSMutableArray *array1 = [NSMutableArray arrayWithObjects:@"1", @"2", @"3", @"4", @"5", nil];
NSMutableArray *array2 = [NSMutableArray arrayWithObjects:@"10", @"11", nil];
NSRange range = NSMakeRange(loc, array2.count); // NOTE: NSMakeRange(NSUInteger loc, NSUInteger len) len must be your array2.cout, or will crash with differs from count of index set
NSIndexSet *indexSet = [NSIndexSet indexSetWithIndexesInRange:range];
[array1 insertObjects:array2 atIndexes:indexSet];
вывод: ["1", "2", "3", "10", "11", "4", "5"]