arrays - 在字典中添加键值对 swift

Question

鉴于此

var applicationPayload =
    [
        "main": [
            "key1": "value1",
            "key2": [
                "inside1": "insideValue1"
            ]
        ]
    ]

如何在 key2 属性中附加或添加某些内容。我希望结果是这样的

[
    "main": [
        "key1": "value1",
        "key2": [
            "newInside2": "newInsideValue2",
            "inside1": "insideValue1"
        ]
    ]
]

我尝试这样做似乎不起作用

applicationPayload["main"]["key2"]["newInside2"] = "newInsideValue2"

Answer 1

您可以创建一个包含 key2 当前值的变量，并在将其重写回原始字典之前对其进行修改:

import Foundation

var applicationPayload =
    [
        "main": [
            "key1": "value1",
            "key2": [
                "inside1": "insideValue1"
            ]
        ]
    ]

print("Before: \(applicationPayload)")

var key2Value = applicationPayload["main"]?["key2"] as! [String: String]
key2Value["newInside2"] = "newInsideValue2"
applicationPayload["main"]?["key2"] = key2Value

print("After: \(applicationPayload)")

输出:

Before: ["main": ["key1": "value1", "key2": ["inside1": "insideValue1"]]]
After: ["main": ["key1": "value1", "key2": ["inside1": "insideValue1", "newInside2": "newInsideValue2"]]]