how to check screen size of iphone 4 and iphone 5 programmatically in swift

I need to replace this Objective-C to Swift. Does anyone have any suggestions on how to transfer it?

if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
{
    CGSize result = [[UIScreen mainScreen] bounds].size;
    if(result.height == 480)
    {
        // iPhone Classic
    }
    if(result.height == 568)
    {
        // iPhone 5
    }
}

Xcode 12.4 • Swift 5.3 or later

extension UIDevice {
    var iPhoneX: Bool { UIScreen.main.nativeBounds.height == 2436 }
    var iPhone: Bool { UIDevice.current.userInterfaceIdiom == .phone }
    var iPad: Bool { UIDevice().userInterfaceIdiom == .pad }
    enum ScreenType: String {
        case iPhones_4_4S = "iPhone 4 or iPhone 4S"
        case iPhones_5_5s_5c_SE = "iPhone 5, iPhone 5s, iPhone 5c or iPhone SE"
        case iPhones_6_6s_7_8 = "iPhone 6, iPhone 6S, iPhone 7 or iPhone 8"
        case iPhones_6Plus_6sPlus_7Plus_8Plus = "iPhone 6 Plus, iPhone 6S Plus, iPhone 7 Plus or iPhone 8 Plus"
        case iPhones_6Plus_6sPlus_7Plus_8Plus_Simulators = "iPhone 6 Plus, iPhone 6S Plus, iPhone 7 Plus or iPhone 8 Plus Simulators"
        case iPhones_X_XS_12MiniSimulator = "iPhone X or iPhone XS or iPhone 12 Mini Simulator"
        case iPhone_XR_11 = "iPhone XR or iPhone 11"
        case iPhone_XSMax_ProMax = "iPhone XS Max or iPhone Pro Max"
        case iPhone_11Pro = "iPhone 11 Pro"
        case iPhone_12Mini = "iPhone 12 Mini"
        case iPhone_12_12Pro = "iPhone 12 or iPhone 12 Pro"
        case iPhone_12ProMax = "iPhone 12 Pro Max"
        case unknown
    }
    var screenType: ScreenType {
        switch UIScreen.main.nativeBounds.height {
        case 1136: return .iPhones_5_5s_5c_SE
        case 1334: return .iPhones_6_6s_7_8
        case 1792: return .iPhone_XR_11
        case 1920: return .iPhones_6Plus_6sPlus_7Plus_8Plus
        case 2208: return .iPhones_6Plus_6sPlus_7Plus_8Plus_Simulators
        case 2340: return .iPhone_12Mini
        case 2426: return .iPhone_11Pro
        case 2436: return .iPhones_X_XS_12MiniSimulator
        case 2532: return .iPhone_12_12Pro
        case 2688: return .iPhone_XSMax_ProMax
        case 2778: return .iPhone_12ProMax
        default: return .unknown
        }
    }
}

print("screenType:", UIDevice.current.screenType)

Alternative solution with UIScreen extension ( iOS 8 and later):

extension UIScreen {

    enum SizeType: CGFloat {
        case Unknown = 0.0
        case iPhone4 = 960.0
        case iPhone5 = 1136.0
        case iPhone6 = 1334.0
        case iPhone6Plus = 1920.0
    }

    var sizeType: SizeType {
        let height = nativeBounds.height
        guard let sizeType = SizeType(rawValue: height) else { return .Unknown }
        return sizeType
    }
}

Usage:

if UIScreen.mainScreen().sizeType == .iPhone4 {
    // Make specific layout for small devices.
}