[英]Map value in particular key in array of dictionary
映射值将特定的键显示在字典数组中的任何位置,并将其替换在同一数组中。
如果字典数组出现,我们需要将pan_card键0更新为1 。
let keyToUpdate = "pan_card"
var arrayOfDictionary = [[String:Any]]()
var firstDict = [String:Any]()
firstDict["passport"] = 0
firstDict["ration_card"] = 0
firstDict["pan_card"] = 0
var arrayDict = [String : Any]()
arrayDict["currentObject"] = firstDict
arrayDict["title"] = "Documents list"
var secondDict = [String:Any]()
secondDict["dl"] = 0
secondDict["voter"] = 0
secondDict["pan_card"] = 0
//let dic = secondDict.filter({ $0.value as! NSNumber != 0})
//secondDict = dic
//print(secondDict)
//let dictionary = ["foo": 1, "bar": 2, "baz": 5]
//
//let newDictionary = dictionary.mapValues { value in
// return value - value
//}
//print(dictionary)
//print(newDictionary)
var arrayDict2 = [String : Any]()
arrayDict2["currentObject"] = secondDict
arrayDict2["title"] = "Second Documents list"
arrayOfDictionary.append(arrayDict)
arrayOfDictionary.append(arrayDict2)
//print(arrayOfDictionary)
for (index, dictionary) in arrayOfDictionary.enumerated() {
let dict = dictionary
let newDictionary = (dict["currentObject"] as![String:Any]).mapValues { value in
return 1
}
arrayOfDictionary[index] = newDictionary
}
print(arrayOfDictionary)
此代码更新currentObject中的每个键
并尝试了这个,但是它添加了新的密钥
for (index, dictionary) in arrayOfDictionary.enumerated() {
var dict = dictionary
// let newDictionary = (dict["currentObject"] as![String:Any]).mapValues { value in
// return 1
// }
var newDictionary = [String: Any]()
for (key, value) in dict["currentObject"] as![String:Any] {
dict[keyToUpdate, default: value] = 1
}
arrayOfDictionary[index] = dict
}
print(arrayOfDictionary)
我需要如下输出
原始值
[["currentObject": ["passport": 0, "pan_card": 0, "ration_card": 0], "title": "Documents list"], ["currentObject": ["pan_card": 0, "dl": 0, "voter": 0], "title": "Second Documents list"]]
更新后
[["currentObject": ["passport": 0, "pan_card": 1, "ration_card": 0], "title": "Documents list"], ["currentObject": ["pan_card": 1, "dl": 0, "voter": 0], "title": "Second Documents list"]]
引用文档链接
我们知道手动迭代和更新值,我们想使用高阶函数来完成。
使用执行更新的递归方法
func update(key:String, in dict: [String:Any], with value: Any) -> [String:Any] {
var out = [String:Any]()
if let _ = dict[key] {
out = dict
out[key] = value
} else {
dict.forEach {
if let innerDict = $0.value as? [String:Any] {
out[$0.key] = update(key: key, in: innerDict, with: value)
} else {
out[$0.key] = $0.value
}
}
}
return out
}
我们可以使用一个简单的map
调用
var original = [["currentObject": ["passport": 0, "pan_card": 0, "ration_card": 0], "title": "Documents list"], ["currentObject": ["pan_card": 0, "dl": 0, "voter": 0], "title": "Second Documents list"]]
let result = original.map{ update(key: "pan_card", in: $0, with: 1)}
update
功能基于此答案
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