Convert MapKit latitude and longitude to DMS format

Question

I am able to determine the latitude and longitude of a location in the center of a map with the following:

func TargetGridReference(outletMapView_PrimaryTargetLo         


        

Answer 1

accepted answer sometimes return invalid values, coordinateToDMS(latitude: 12.99999999, longitude: 0.0) returns latitude 12° 59' 60.0000" N

enum GeoFormat {
    case D
    case DM
    case DMS
}
func dms(value: Double, format: GeoFormat)->String {
    let sign = value < 0.0 ? -1 : 1
    let value = abs(value)
    switch format {
    case .D:
        return String(format: "%+15.10f°", value * Double(sign))
    case .DM:
        var deg = Int(value)
        var min = round((value - Double(deg)) * 60 * 10000000) * 0.0000001
        if min < 60.0 {} else {
            min -= 60.0
            deg += 1
        }
        return String(format: "%+4d°%010.7f′", deg * sign, min)
    case .DMS:
        var deg = Int(value)
        let _min = (value - Double(deg)) * 60
        var min = Int(_min)
        var sec = round((_min - Double(min)) * 60 * 10000) * 0.0001
        if sec < 60.0 {} else {
            sec -= 60.0
            min += 1
        }
        if min < 60 {} else {
            min -= 60
            deg += 1
        }
        return String(format: "%+4d°%02d′%07.4f″", deg * sign, min, sec)
    }
}

let value = -12.999999997222222
print(dms(value: value, format: .D))
print(dms(value: value, format: .DM))
print(dms(value: value, format: .DMS))

prints, as required

 -12.9999999972°
 -12°59.9999998′
 -13°00′00.0000″