使用Newtonsoft.Json反序列化復雜JSON-VisualBasic

需要幫助使用 Visual Basic 和 Newtonsoft.Json 庫反序列化復雜的 json 檔案。這是 Json 檔案的示例：

{
"value":  [
              {
                  "Id":  12345,
                  "Name":  "Test",
                  "CardCount":  0,
                  "DailySpendLimit":  0.00,
                  "WeeklySpendLimit":  50.00,
                  "MonthlySpendLimit":  100.00,
                  "YearlySpendLimit":  1000.00,
                  "LifetimeSpendLimit":  0.00,                      
                  "MerchantCategories":  [
                                             "@{Id=11111; Name=Associations \u0026 Organizations; Description=Post Office, local and federal government services, religious organizations.; TransactionLimit=0.00; DailySpendLimit=0.00; WeeklySpendLimit=0.00; MonthlySpendLimit=0.00; YearlySpendLimit=0.00; LifetimeSpendLimit=0.00}",
                                             "@{Id=22222; Name=Automotive Dealers; Description=Vehicle dealerships (car, RV, motorcycle, boat, recreational).; TransactionLimit=0.00; DailySpendLimit=0.00; WeeklySpendLimit=0.00; MonthlySpendLimit=0.00; YearlySpendLimit=0.00; LifetimeSpendLimit=0.00}"                                              
                                         ]
              }
          ],
"Count":  1

}

我有設定課程：

Public Class TEST_AdvRules
<JsonProperty("value")>
Public Property ValueDetails As ValueList()
Public Class ValueList
    <JsonProperty("Id")>
    Public Property RuleId As Integer
    <JsonProperty("Name")>
    Public Property RuleName As String = ""
    Public Property CardCount As Integer
    Public Property DailySpendLimit As Double
    Public Property WeeklySpendLimit As Double
    Public Property MonthlySpendLimit As Double
    Public Property YearlySpendLimit As Double
    Public Property LifetimeSpendLimit As Double
    <JsonProperty("MerchantCategories")>
    Public Property MerchantCategories() As List(Of MerchantCategoriesList)       
End Class
Public Class MerchantCategoriesList
    Public Property Id As Integer
    Public Property Name As String = ""
    Public Property Description As String = ""
    Public Property TransactionLimit As Double
    Public Property DailySpendLimit As Double
    Public Property WeeklySpendLimit As Double
    Public Property MonthlySpendLimit As Double
    Public Property YearlySpendLimit As Double
    Public Property LifetimeSpendLimit As Double
End Class

結束類

反序列化代碼：

Dim jsonStringP = IO.File.ReadAllText(PathJson & SecFileName)
    Dim serSettings = New JsonSerializerSettings()
    serSettings.ContractResolver = New CamelCasePropertyNamesContractResolver()

    Dim RulesPEX = JsonConvert.DeserializeObject(Of TEST_AdvRules)(jsonStringP, serSettings)

但它在反序列化行出錯 - 無法轉換 MerchantCategories。我從來沒有用[ "@ array sequence

uj5u.com熱心網友回復：

問題是 MerchantCategories 是一個字串集合。您必須使用自定義字串分析器將每個字串轉換為物件。上次我使用 Vb.net 是在 10 多年前，所以我可以在 C# 中給你一個解決方案，你的部分是將它轉換為 VB.Net。我不想在我的機器上安裝 VB.NET 編譯器。

using Newtonsoft.Json;

var jsonObject = JObject.Parse(jsonStringP);
var jsonArr=new JArray();
    
    foreach (var item in   (JArray) jsonObject["value"][0]["MerchantCategories"])
    {
        jsonArr.Add(ConvertToJObject(item.ToString()));
    }
    jsonObject["value"][0]["MerchantCategories"]=jsonArr;
    TEST_AdvRules RulesPEX = jsonObject.ToObject<TEST_AdvRules>();

此函式將字串轉換為 JObject

public JObject ConvertToJObject(string str)
{
    var strStart=str.IndexOf("{") 1;
    var strEnd=str.IndexOf("}")-2;
    var arr = str.Substring(strStart, strEnd).Split(";").Select(c => c.Split("="));
    var jObj = new JObject();
    foreach (var item in arr)
        jObj.Add(new JProperty(item[0].Trim(), item[1].Trim()));

    return jObj;
}

uj5u.com熱心網友回復：

讓 Visual Studio 為您創建類：

• 將整個 json 檔案內容復制到剪貼板
• 在VS中，添加一個新的空類->編輯->選擇性粘貼->將json粘貼為類

我傾向于添加一個共享的Read-Method 以便于構建。當然，您可以根據需要重命名您的課程 :-)

我在德國VS，但你明白了:-)

uj5u.com熱心網友回復：

將 Serge 的答案翻譯成 VB（注意未經測驗的代碼，因此可能存在一些小錯誤）...

Imports Newtonsoft.Json

'...

Dim jsonObject = JObject.Parse(jsonStringP)
Dim jsonArr = new JArray()

For Each item In CType(jsonObject("value")(0)("MerchantCategories"), JArray)
    jsonArr.Add(ConvertToJObject(item.ToString()))
Next

jsonObject("value")(0)("MerchantCategories") = jsonArr
Dim RulesPEX As TEST_AdvRules = jsonObject.ToObject(Of TEST_AdvRules)()

和

Public Function ConvertToJOBject(ByVal str As String) As JObject
    Dim strStart = str.IndexOf("{")   1
    Dim strEnd = str.IndexOf("}") - 2

    Dim arr = str.Substring(strStart, strEnd).Split(";").Select(Function(c) c.Split("="))
    Dim jObj = New JObject()

    For Each item In arr
        jObj.Add(New JProperty(item(0).Trim(), item(1).Trim()))
    Next

    Return jObj
End Function

標籤：数组jsonVB.netjson.net

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