Learning Swift from scratch (day 34)--What is a static property?

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I'll start by designing a class: There's a Account (bank account) class, assuming it has 3 Properties: Amount (account amount), InterestRate (interest rate) and owner (account name).

in this 3 amount and owner interestrate are all the same.

Amount and the owner attribute is related to the account individual, called Instance Properties . the interestrate attribute is independent of the individual, or shared by all account individuals, which is called a static property or type attribute .

Object-oriented types (structs, enumerations, and classes) can all define static properties, and their syntax formats are as follows:

struct struct Name {//define struct body, can define static storage property and static computed property in struct
static VAR (or let) store property = "XXX"
...
Static Var computed property name: property data type {
get {
Return computed property value
}
Set (new property value) {
...
}
}
}

enum Enumeration Name {// Define an enumeration, which cannot be used to define an instance store property, but can define a static storage property, or you can define a static computed property

static VAR (or let) store property = "XXX"
...
Static Var computed property name: property data type {
get {
Return computed property value
}
Set (new property value) {
...
}
}
}

Class class Name {//define classes in which you can define not only instance store properties, but also static storage properties
Staticvar (or let) store property = "XXX"
...
Class (or Static) var computed property name: property data type {
get {
Return computed property value
}
Set (new property value) {
...
}
}
}
struct static computed properties can also be read-only, with the following syntax:
Static Var computed property name: property data type {
Return computed property value
}

See a Account examples of struct static properties:

struct Account {//Define account structure body

var amount:double = 0.0//Account Amount
var owner:string = ""//Account name

static var interestrate:double = 0.0668//define the stored property interestrate interest rate

static Var staticprop:double {//define statically computed properties Staticprop
return interestrate * 1_000_000
}

var instanceprop:double {//Define instance calculation properties Instanceprop
Return Account.interestrate * Amount
}
}

accessing static properties
Print (Account.staticprop)

var myAccount = account ()
accessing instance Properties
Myaccount.amount =1_000_000
accessing static properties
Print (Myaccount.instanceprop

)

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Learning Swift from scratch (day 34)--What is a static property?