Question

我有一个Swift词典，我试图完全删除一个条目。我的代码如下：

import UIKit

var questions: [[String:Any]] = [
    [
        "question": "What is the capital of Alabama?",
        "answer": "Montgomery"
    ],
    [
        "question": "What is the capital of Alaska?",
        "answer": "Juneau"
    ]
 ]

var ask1 = questions[0]
var ask2 = ask1["question"]

print(ask2!) // What is the capital of Alabama?

questions[0].removeAll()

ask1 = questions[0] // [:]
ask2 = ask1["question"] // nil - Should be "What is the capital of Alaska?"

我使用问题[0] .removeAll（）来删除条目，但它留下一个空条目。如何完全删除条目以便没有跟踪？

Answer 1

这种行为没有任何问题，你告诉编译器删除Dictionary中的所有元素并且它工作正常：

questions[0].removeAll()

但您要声明Array<Dictionary<String, Any>>或简写语法[[String: Any]]，如果要删除Dictionary，还需要从数组中删除该条目，请参阅以下代码：

var questions: [[String: Any]] = [
   [
    "question": "What is the capital of Alabama?",
    "answer": "Montgomery"
   ],
   [
    "question": "What is the capital of Alaska?",
    "answer": "Juneau"
   ]
]

var ask1 = questions[0]
var ask2 = ask1["question"]

print(ask2!) // What is the capital of Alabama?

questions[0].removeAll()

questions.removeAtIndex(0) // removes the entry from the array in position 0

ask1 = questions[0] // ["answer": "Juneau", "question": "What is the capital of Alaska?"]
ask2 = ask1["question"] // "What is the capital of Alaska?"

我希望这对你有所帮助。

Swift Dictionary：无法完全删除条目

1 个答案: