Accessing static variables of a model class using reflection

Question

I have a model class that contains some static variables and properties. In Runtime I can get the properties;

let instance = entity.init()

let mirror = Mirror(reflecting:instance)

var propertyStrings = [String]()

for (propertyName, childMirror) in mirror.children {

}

But I want to get static variables of the class as a list too. So how can I get the list of static variable's names and values ? Here is my model class' structure :

class ActionModel: NSObject {

static let kLastModified = "LastModified"
static let kEntityName = "EntityName"
static let kIdentifier = "Id"


var lastModified: Int64
var entityName: String?
var identifier : PrimaryKeyString

score 18 · Accepted Answer · answered Feb 10 '16 at 07:50

18

Getting type properties via reflection is not supported yet. You can see this by inspecting the displayStyle of the Mirror you get if you pass the class object to the initializer:

let mirror = Mirror(reflecting: ActionModel.self)
print(mirror.displayStyle)    // nil

answered Feb 10 '16 at 07:50

Alberto Doda

281
2
6

It looks like this is unchanged seven years later? – Sören Kuklau May 03 '23 at 15:59

score 9 · Answer 2 · answered Feb 21 '18 at 13:13

You might use the Objective-c runtime, especially the function class_copyPropertyList which describes the properties declared by a class. Example:

import Foundation

class Foo:NSObject {
    @objc static var prop1: String? = "Hello I am prop1!"
    @objc static var prop2: String? = "Hello I am prop2!"
}

var count: CUnsignedInt = 0
let methods = class_copyPropertyList(object_getClass(Foo.self), &count)!
for i in 0 ..< count {
    let selector = property_getName(methods.advanced(by: Int(i)).pointee)
    if let key = String(cString: selector, encoding: .utf8) {
        let res = Foo.value(forKey: key)
        print("name: \(key), value: \(res ?? "")")
    }
}

Great answer!. Saved me alot of time – Oz Shabat Jun 01 '22 at 09:40 — Oz Shabat, Jun 01 '22 at 09:40

Accessing static variables of a model class using reflection

2 Answers2

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