Question

我正在尝试将数组添加到字典中，但出现此错误：

无法将类型[[[String：String]]]的值转换为预期的字典值类型'Array

这是我的实现方式：

class PdfUpload(APIView):

parser_classes = (MultiPartParser, FormParser,)

def get(self, request):
    return Response([PdfSerializer(file).data for file in Pdf.objects.all()])

def post(self,request):
    payload=(request.data,request.FILES)
    print("Hello")
    print(payload)
    serializer=PdfSerializer(data=payload)

    if serializer.is_valid():
        serializer.save()
        return Response("File Saved in Backend",status=status.HTTP_201_CREATED)
    return Response(serializer.errors,status=status.HTTP_400_BAD_REQUEST)

在此行let dicContent:[String: String] = ["Alabama": "Montgomery", "Alaska":"Juneau","Arizona":"Phoenix"] var myArray:Array = [[String: String]]() myArray.append(dicContent) let mainDict:[String:Array] = ["MainDictionary": myArray]上出现错误

你们中的任何人可能都知道为什么我会收到此错误或解决方法？

Answer 1

请勿使用Array关键字来定义字典类型。尝试按照以下步骤解决您的问题：

let dicContent: [String: String] = ["Alabama": "Montgomery", "Alaska":"Juneau","Arizona":"Phoenix"]
var myArray = [[String: String]]()
myArray.append(dicContent)
let mainDict: [String: [[String: String]]] = ["MainDictionary": myArray]

在这种情况下，变量的类型可以隐式定义，因此您的代码可以简化为以下形式：

let dicContent = ["Alabama": "Montgomery", "Alaska":"Juneau","Arizona":"Phoenix"]
let mainDict = ["MainDictionary": [dicContent]]

Answer 2

错误提示，您已将mainDict声明为

let mainDict:[String:Array]

，但未指定Array的内容。您可以尝试以下方法之一来解决此问题。

尝试：

let dicContent:[String: String] = ["Alabama": "Montgomery", "Alaska":"Juneau","Arizona":"Phoenix"]
var myArray = [[String: String]]()
myArray.append(dicContent)
let mainDict:[String:[[String: String]]] = ["MainDictionary": myArray]

或者如果您想使用Array关键字，可以按照以下步骤操作：

let dicContent:[String: String] = ["Alabama": "Montgomery", "Alaska":"Juneau","Arizona":"Phoenix"]
var myArray = Array<[String: String]>()
myArray.append(dicContent)
let mainDict:[String:Array<[String:String]>] = ["MainDictionary": myArray]

或者简单地

let mainDict = ["MainDictionary": myArray]

使用数组关键字时，需要指定数组将在<...>

中保留的对象类型。

Answer 3

let dicContent:[String: String] = ["Alabama": "Montgomery", 
"Alaska":"Juneau","Arizona":"Phoenix"]
var myArray  = [[String: String]]()
myArray.append(dicContent)
let mainDict:[String:Any] = ["MainDictionary": myArray]
let getArrayBack = mainDict["MainDictionary"] as! [[String:String]]

如何将数组添加到字典？

3 个答案: