Using Iskindofclass with Swift

Using isKindOfClass with Swift

The proper Swift operator is is:

if touch.view is UIPickerView {
    // touch.view is of type UIPickerView
}

Of course, if you also need to assign the view to a new constant, then the if let ... as? ... syntax is your boy, as Kevin mentioned. But if you don't need the value and only need to check the type, then you should use the is operator.

Using isKindOf in Swift

The substitute for isKindOf in Swift3 is:

if annotation is MKUserLocation {
    return nil
}

isKindOfClass method to check Swift ViewController in Objective C

Because of the bug in swift, @Freerunnering answer will not work.
As a work around, we can get the class name as string and then do the string match.

if ([NSStringFromClass([AViewController class] isEqualToString:@"ProjectName.AViewController"]) {

}

Is there a difference between is and isKindOfClass()?

Yes there is a difference: is works with any class in Swift, whereas isKindOfClass() works only with those classes that are subclasses of NSObject or otherwise implement NSObjectProtocol.

Check isKindOfClass to Dictionary in Swift

This is because isKindOfClass requires an AnyClass type – that is, a type that is a class. Dictionaries aren’t classes, they’re structs, and thus can’t be held by an AnyObject.

If you switch your code to application.isKindOfClass(NSDictionary) it should work (work in the sense that it will compile, and check if the type is an NSDictionary).

swift can't call isKindOfClass with String

isKindOfClass() works only with classes that are subclass of NSObject.

You can use fieldValue is String.

if fieldValue is String {
  // do something with string
}

Difference between Swift is and isKindOfClass()?

I will assume that the .isKindOfClass() is the instance method from Cocoa.

• The right side of is can be any type or protocol, whereas the argument of .isKindOfClass() must be a reference type (i.e. class). You can also test for conformance to an @objc protocol using .conformsToProtocol() instead of .isKindOfClass() in the same way.
• The left side of is is any expression, whereas the receiver of .isKindOfClass() must be an object reference. The compiler will complain if the compile-time class of the expression is not known to support .isKindOfClass(), but you can overcome this by casting the left side to AnyObject. All Swift classes actually support .isKindOfClass() at runtime.
• The right side of is is a type that must be hard-coded at compile-time. The argument of .isKindOfClass() can be a variable or other expression whose value is computed at runtime.

What is the proper way to use if _ is _ or .isKind(of: )

public func isKind(of aClass: AnyClass) -> Bool

This function requires AnyClass as argument, you must pass a class, using .self

    mapView.annotations.forEach {
        if !$0.isKind(of: MKUserLocation.self) {
            self.mapView.removeAnnotation($0)
        }
    }

When use is, you must wrap the expression with parentheses:

    mapView.annotations.forEach {
        if !($0 is MKUserLocation) {
            self.mapView.removeAnnotation($0)
        }
    }

You are checking boolean value of $0, not the is expression, hence the error.

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