Question

使用其他JSON-API时，可以方便地在应用程序和调用服务器时保持属性的一致性对于这个例子：

class Picture: NSManagedObject {

    @NSManaged var copyright: String
    @NSManaged var likes: NSNumber
}


func postToServer() {
   let newPicture = Picture(copyright: "haaakon", likes:433)

   let arguments = @{  
       newPicture.copyright.selectorName : newPicture.copyright,
       newPicture.likes.selectorName : newPicture.likes 
   }

   println(arguments)
}

println应该给出这个输出：

{ "copyright": "haaakon", "likes": "433" }

如何在给定属性上创建扩展（或其他解决方案）时如何进行基本相同：

NSStringFromSelector(Selector(newPicture.copyright)) // returns "copyright"
newPicture.copyright.selectorName                    // returns "copyright"

Answer 1

试试这个：

extension Picture{
    func dictionary() -> Dictionary<String, AnyObject> {
        var outCount: CUnsignedInt = 0
        let properties: UnsafeMutablePointer<objc_property_t> = class_copyPropertyList(self.dynamicType, &outCount)

        var result: Dictionary<String, AnyObject> = Dictionary()

        for var i = 0; i < Int(outCount); i++ {
            var property : NSString! = NSString(CString: property_getName(properties[i]), encoding: NSUTF8StringEncoding)
            result[property] = self.valueForKey(property)
        }

        return result
    }
}

如何将选择器名称作为Swift中对象的属性？

1 个答案: