将1 Dictionary中的项添加到另一个Dictionary -Swift iOS9

Question

1. 我有一个名为buttonPressed的按钮.
2. 我有一个带有苏打水的sodaArray属性.
3. 我有一个空的foodDict属性,后来我用键/值对填充.
4. 我有一个空的sodaMachineArray属性我必须把苏打水放入.我使用一个函数将sodas附加到它中,然后使用另一个函数为它们分配键/值对以添加到foodDict中.我将这一切都放在名为addSodas()的1个函数中.

在buttonPressed操作中,我运行addSodas()函数.第二,我用不同的值填充foodDict.我需要将两个词典附加在一起,以便foodDict中包含所有苏打水,并附上当前的值.

我遇到的问题是addSodas()函数必须先行(我别无选择).既然那是第一个,而foodDict是第二个,我如何结合两个词典？

class ViewController: UIViewController {

//soda values already in the sodaArray
var sodaArray = ["Coke", "Pepsi", "Gingerale"]

//I add the soda values to this empty array(I have no choice)
var sodaMachineArray = [String]()

//This is a food dictionary I want to add the sodas in
var foodDict = [String: AnyObject]()


override func viewDidLoad() {
    super.viewDidLoad()
}


//Function to add sodas to the foodDict
func addSodas(){

    //Here I append the sodas into the sodaMachineArray
    for soda in self.sodaArray {
        self.sodaMachineArray.append(soda)
    }

    //I take the sodaMachineArray, grab each index, cast it as a String, and use that as the Key for the key/value pair
    for (index, value) in self.sodaMachineArray.enumerate(){
        self.foodDict[String(index)] = value
    }
    print("\nA. \(self.foodDict)\n")
}


//Button
@IBAction func buttonPressed(sender: UIButton) {

    self.addSodas()
    print("\nB. \(self.foodDict)\n")

    self.foodDict = ["KFC": "Chicken", "PizzaHut": "Pizza", "McDonalds":"Burger"]
    print("\nD. food and soda key/values should print here: \(self.foodDict)???\n")

    /*I need the final outcome to look like this  
self.foodDict = ["0": Coke, "McDonalds": Burger, "1": Pepsi, "KFC": Chicken, "2": Gingerale, "PizzaHut": Pizza]*/
        }
    }

顺便说一下,我知道我可以使用下面的方法扩展Dictionary,但在这种情况下没有用,因为addSodas()函数必须在foodDict填满之前到来.此扩展程序有效,但我无法将其用于我的方案.

extension Dictionary {
    mutating func appendThisDictWithKeyValuePairsFromAnotherDict(anotherDict:Dictionary) {
        for (key,value) in anotherDict {
            self.updateValue(value, forKey:key)
        }
    }
}

Answer 1

问题:

self.foodDict = ["KFC": "Chicken", "PizzaHut": "Pizza", "McDonalds":"Burger"]

此行创建新数组并分配这些值.

解:

1. 拥有持有关键值的临时财产["KFC":"Chicken","PizzaHut":"Pizza","McDonalds":"Burger"].
2. 迭代并将其分配给FoodDict.

例:

//Button
@IBAction func buttonPressed(sender: UIButton) {

    self.addSodas()
    print("\nB. \(self.foodDict)\n")

    var tempFoodDict = ["KFC": "Chicken", "PizzaHut": "Pizza", "McDonalds":"Burger"]
    for (key, value) in tempFoodDict {
        self.foodDict[String(key)] = String(value)
    }
    print("\nD. food and soda key/values should print here: \(self.foodDict)???\n")
}