ios - NSPredicate 对象模型数组过滤器无法在 Swift 4.0 中崩溃

Question

1. 我在 swift 4.0 中工作，我在 MutableArray 中有模型对象， NSPredicate 不工作。

                //Here is code
               //Model class:
               class Modelclass: NSObject
               {
                   var firstName:String!
                   var lastName:String!
               }
   
               // Viewcontroller doing predicate:
               let ary = NSMutableArray()
   
               let userModel          = Modelclass()
               userModel.firstName    = "Arrya"
               userModel.lastName     = "stark"
               ary.add(userModel)
   
               let commitPredicate = NSPredicate(format: "firstName == %@", "Arrya")
               let resultAry       = ary.filtered(using: commitPredicate)
               print(resultAry)
   

Answer 1

我解决了这个问题， 解决方案一:

    //I just added below code in model class

    extension Modelclass {
        @objc override func value(forKey key: String) -> Any? {
            switch key {
            case "firstName":
                return firstName
            case "lastName":
                return lastName
            default:
                return nil
            }
        } 
   }

解决方案 2:

在变量前添加@objc:

        class Modelclass: NSObject
        {
            @objc var firstName:String!
            @objc var lastName:String!

        }