Swift Tutorial - Swift Initialization

We initialize an instance to get the instance ready for use.

class Person {
    var name: String = "Name"
    var age:Int = 0
}

var p = Person()

p.name = "Jack"
p.age = 4

In the code above we called the default initializer by using the class name followed by parentheses: Person().

Custom initializer

We can use init() to override the default initializer. In the custom initializer we can set the default property values in the class declaration.

class Person {
    var name: String
    var age:Int
    init() {
        self.name = "Name"
        self.age = 0
    }
}

In the code above we overrode the default initializer init() to set the default property of name to Name and of age to 0.

Initializer with Parameters

You can add parameters to custom initializers.

class Person {
    var name: String
    var age:Int

    init() {
        self.name = "Name"
        self.age = 0
    }

    init(name:String, age:Int) {
        self.name = name
        self.age = age
    }

}
var p = Person(name: "Jack", age: 4)

De-initialization

When an instance is no longer need, Swift deallocates the instance and frees up the instance resources.

class Person {
    deinit {
        //release any resources
    }
}