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vb.net - 从 ALPHA VANTAGE VB.NET 解析带有句点的 JSON 数据

问题描述

我正在尝试从 alpha vantage 解析数据，但对象内部的属性中有一个句点，导致它什么也不返回。

    Public Sub GetPKGStats(symbol As String)
        Dim StatsUrl, result, Open, Close, Volume, LastRefreshed As String
        Dim JSONresult As JObject     
        Dim results As List(Of JToken)

        result = "{""Meta Data"": {""1. Information"": ""Daily Prices (open, high, low, close) and Volumes"",""2. Symbol"": ""PKG"",""3. Last Refreshed"": ""2021-02-16"",""4. Output Size"": ""Compact"",""5. Time Zone"": ""US/Eastern""},""Time Series (Daily)"": {""2021-02-16"": {""1. open"": ""133.4500"",""2. high"": ""133.5650"",""3. low"": ""131.5000"",""4. close"": ""133.0400"",""5. volume"": ""638371""},""2021-02-12"": {""1. open"": ""131.0400"",""2. high"": ""133.9200"",""3. low"": ""131.0400"",""4. close"": ""133.1800"",""5. volume"": ""562984""},""2021-02-11"": {""1. open"": ""133.9900"",""2. high"": ""134.4900"",""3. low"": ""130.3700"",""4. close"": ""131.1700"",""5. volume"": ""768588""}}}"
    JSONresult = JObject.Parse(result)   
    results = JSONresult.Children().ToList()

     For each item As JProperty In results
         LastRefreshed =  item.First.SelectToken("1.Information")
     Next    
End Sub

这不会返回任何内容，但是如果我从“元数据”对象的第一个属性中删除句点，返回就好了。我正在考虑对返回的字符串进行替换，但如果它们中有句点，这可能会影响值。

这是一个缩短的 JSON 字符串示例。

{
"Meta Data": {
    "1. Information": "Daily Prices (open, high, low, close) and Volumes",
    "2. Symbol": "PKG",
    "3. Last Refreshed": "2021-02-16",
    "4. Output Size": "Compact",
    "5. Time Zone": "US/Eastern"
},
"Time Series (Daily)": {
    "2021-02-16": {
        "1. open": "133.4500",
        "2. high": "133.5650",
        "3. low": "131.5000",
        "4. close": "133.0400",
        "5. volume": "638371"
    },
    "2021-02-12": {
        "1. open": "131.0400",
        "2. high": "133.9200",
        "3. low": "131.0400",
        "4. close": "133.1800",
        "5. volume": "562984"
    },
    "2021-02-11": {
        "1. open": "133.9900",
        "2. high": "134.4900",
        "3. low": "130.3700",
        "4. close": "131.1700",
        "5. volume": "768588"
    },
    "2021-02-10": {
        "1. open": "132.9800",
        "2. high": "134.1200",
        "3. low": "132.5200",
        "4. close": "133.7900",
        "5. volume": "715949"
    }
  }
}

有没有办法只在接收字符串变量“results”中的字符串时更改属性名称

标签： vb.netjson.net

解决方案

如果你像这样构造你的类，使用 JsonProperty 来映射属性，它可以工作：

Public Class MetaData

    <JsonProperty("1. Information")>
    Public Property Information As String

    <JsonProperty("2. Symbol")>
    Public Property Symbol As String

    <JsonProperty("3. Last Refreshed")>
    Public Property LastRefreshed As String

    <JsonProperty("4. Output Size")>
    Public Property OutputSize As String

    <JsonProperty("5. Time Zone")>
    Public Property TimeZone As String

End Class

Public Class TimeSeriesData
    
    <JsonProperty("1. open")>
    Public Property Open As Decimal

    <JsonProperty("2. high")>
    Public Property High As Decimal

    <JsonProperty("3. low")>
    Public Property Low As Decimal

    <JsonProperty("4. close")>
    Public Property Close As Decimal

    <JsonProperty("5. volume")>
    Public Property Volume As Integer

End Class

设置类后，您将使用 DeserializeObject 解析相应的对象：

Dim obj = JObject.Parse(results)
Dim meta = JsonConvert.DeserializeObject(Of MetaData)(obj.First.First.ToString())
Dim dailyTimeSeries = JsonConvert.DeserializeObject(Of Dictionary(Of DateTime, TimeSeriesData))(obj.Last.First.ToString())

演示：https ://dotnetfiddle.net/R1WXok

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