Setting multiple integers for "If" statement test value

Question

I am trying to set multiple integer tests for a single variable in the if statement. The logical operators won't work due to the fact that they must be boolean.

For example:

if self.nodeAtPoint(location) == self.fake {
    groundspeed = 35.0
    self.button1value++

    if(button1value == 2) {
      groundspeed = 5.0
    }

    if(button1value == 4){
        groundspeed = 5.0
    }

    if(button1value == 6) {
        groundspeed = 5.0
    }
}

The goal is to be able to put all of the even numbers shown into just one if statement.

Answer 1

If we just want to check whether or not button1value is even, we can do that using the modulo (%) operator:

if button1value % 2 == 0 {
    // button1value is even
    groundspeed = 5.0
}

If we're checking for some other sort of set, we can use a switch statement:

switch button1value {
    case 2,4,6:
        // button1value is 2, 4, or 6
        groundspeed = 5.0
    default:
        // button1value is something else
}

We can do other neat tricks with Swift's switch statement too, if we want:

switch (button1value % 2, button1value % 3) {
    case (0,0):
        // button1value is an even multiple of 3 (6,12,18...)
    case (0,_):
        // button1value is an even number not a multiple of three (2,4,8,10,14...)
    case (_,0):
        // button1value is an odd multiple of three (3,9,15,21...)
    default:
        // button1value is none of the above: (1,5,7,11...)
}

Answer 2

Check and accept nhgrif's answer for a better variant. But just for the sake of completeness if you want to keep your way, you can use the logical OR operator ||

if(button1value == 2 || button1value == 4 || button1value == 6) {
    groundspeed = 5.0
}

That checks if any of the given boolean-values is true.

There is also a logical AND operator &&.