Question

您好我正在尝试从Json字符串中获取所有项目的列表请温柔我是一个完全编程虚拟大声笑我一直在搜索，直到我脸上都是蓝色的，但在How to Parse Json children in VB.NET Newtonsoft找到了最好的例子但是在尝试了所有的后，我只能从“结果”中得到第一批项目但我需要所有来自“nilfromhere”的物品这是Json字符串看起来像

{ “jsonrpc”： “2.0”， “结果”：[{ “RESULT1”： “noproblem1”， “结果2”： “noproblem2”， “nilfromhere”：[{ “thisone”：000， “andthis”： “nodice”，“needthis”：0.0，“andthis”：1}]}]，“maybethis”：1}

这就是我所拥有的（我已经尝试过切换它们但仍然只获得前面的结果）

 Dim strJson As String = txtTester.Text
    Dim obj As JObject = JObject.Parse(strJson)
    Dim results As List(Of JToken) = obj.Children().ToList
    Dim strStart As String = ""
    Dim strOutput1 As String = ""
    Dim strOutput2 As String = ""
    For Each item As JProperty In results
        item.CreateReader()
        Select Case item.Name
            Case "jsonrpc"
                Dim strVersion As String = ""
                strVersion = item.Value.ToString
                strStart = strVersion  'Returns 2.0 so no need to be a double etc
            Case "result"
                Dim Result1 As String = ""
                Dim Result2 As String = ""
                'Dim NilFromHere as String >>> Cant convert an Array to string error when tried up here
                '~~> All these work fine below up to the nilfromhere string
                For Each resultItem As JObject In item.Values
                    Result1 = resultItem("result1") 'Returns "noproblem1"
                    Result2 = resultItem("result2") 'Returns "noproblem2"
                    ' Dim ResultTry As Object = resultItem("nilfromhere").ToString '= Error as expected!
                    ' Dim ResultTry2 As Object = resultItem("thisone").ToString '= Error as expected!
                Next
                strOutput1 += Result1 + vbTab + Result2 + vbCrLf
                'Below returns nothing but no errors! I need all the items from "nilfromhere" 
            Case "nilfromhere" ' Tried this here as it looks identical to the first one
                Dim Thisone As Object = Nothing 'Tried object because its an integer but 2.0 works ok above
                Dim AndThis As String = ""
                'Get nothing here
                For Each Iwish As JObject In item.Values
                    Thisone = Iwish("thisone").ToString 'Number values but dont think thats the problem?
                    AndThis = Iwish("andthis").ToString
                    'Other Items etc
                Next
                strOutput2 += Thisone + vbTab + AndThis + vbCrLf
                '*** Try as an array but returns same as above - Nothing but no errors!
                Dim IwishArray As JArray = item.Value    'Get the top-level array?
                For Each IwishArrayItem As JObject In IwishArray.Values
                    Thisone = IwishArrayItem("thisone")
                    AndThis = IwishArrayItem("thisone")
                Next
                strOutput2 += Thisone + vbTab + AndThis + vbCrLf
        End Select
    Next
    MsgBox(strStart)
    MsgBox(strOutput1)
    MsgBox(strOutput2)

如果有人能帮助我，我真的很感激非常感谢提前戴夫

Answer 1

不要手动解析json，而应该让Json库完成所有工作。

您可以通过定义与您尝试解析的Json匹配的类结构，然后要求json库将json字符串反序列化为该类结构来实现。它将处理所有必要的工作，例如类型转换和实例化数组或对象列表，而无需您进行任何额外的工作。

这是一个基于你的json字符串的工作示例（我必须更改第二个，然后将此更改为andthis1以使其正常工作）：

顶级课程：

public class TopLevel
{
    public string jsonrpc { get; set; }
    public List<SecondLevel> result { get; set; }
}

第二级课程（包含在上面的数组结果中）：

public class SecondLevel
{
    public string result1 { get; set; }
    public string result2 { get; set; }
    public List<ThirdLevel> nilfromhere { get; set; }
    public int maybethis { get; set; }
}

第三级类（存储在nillfromhere中的对象数组）：

public class ThirdLevel
{
    public int thisone { get; set; }
    public string andthis { get; set; }
    public decimal needthis { get; set; }
    public int andthis1 { get; set; }
}

最后，反序列化代码：

const string json = @"{""jsonrpc"":""2.0"",""result"":[{""result1"":""noproblem1"",""result2"":""noproblem2"",""nilfromhere"":[{""thisone"":000,""andthis"":""nodice"",""needthis"":0.0,""andthis1"":1}]}],""maybethis"":1}";

var jsonObject = Newtonsoft.Json.JsonConvert.DeserializeObject<TopLevel>(json);

Debug.WriteLine(jsonObject.result[0].nilfromhere[0].andthis);

如何使用vbnet获取Json List项目

1 个答案: