我正在尝试使用单声道在Raspbian下使用Newtosoft.Json在JObject中反序列化JSON字符串。但它无法反序列化Float。
Dim myStationJSON As String
myStationJSON = myWC.DownloadString("https://api.netatmo.com/api/getstationsdata?access_token=" & myToken.Token.access_token)
Dim myJSON As Newtonsoft.Json.Linq.JObject
Dim myStationName As String = ""
Dim opts As New Newtonsoft.Json.JsonSerializerSettings
opts.FloatParseHandling = Newtonsoft.Json.FloatParseHandling.Double
myJSON = Newtonsoft.Json.JsonConvert.DeserializeObject(myStationJSON, opts)
我得到了这个例外：
Newtonsoft.Json.JsonReaderException：输入字符串'-0.2'不是有效数字。路径'body.devices [0] .modules [0] .dashboard_data.Temperature'，第1行，第329位。 at Newtonsoft.Json.JsonTextReader.ParseNumber（ReadType readType）[0x00000] in：0 at Newtonsoft.Json.JsonTextReader.ParseValue（）[0x00000] in：0 在Newtonsoft.Json.JsonTextReader.Read（）[0x00000] in：0 在Newtonsoft.Json.JsonWriter.WriteToken（Newtonsoft.Json.JsonReader reader，Boolean writeChildren，Boolean writeDateConstructorAsDate，Boolean writeComments）[0x00000] in：0 at Newtonsoft.Json.Linq.JTokenWriter.WriteToken（Newtonsoft.Json.JsonReader reader，Boolean writeChildren，Boolean writeDateConstructorAsDate，Boolean writeComments）[0x00000] in：0 在Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateJObject（Newtonsoft.Json.JsonReader reader）[0x00000] in：0 在Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject（Newtonsoft.Json.JsonReader reader，System.Type objectType，Newtonsoft.Json.Serialization.JsonContract contract，Newtonsoft.Json.Serialization.JsonProperty成员，Newtonsoft.Json.Serialization.JsonContainerContract containerContract， Newtonsoft.Json.Serialization.JsonProperty containerMember，System.Object existingValue）[0x00000] in：0 在Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal（Newtonsoft.Json.JsonReader reader，System.Type objectType，Newtonsoft.Json.Serialization.JsonContract contract，Newtonsoft.Json.Serialization.JsonProperty member，Newtonsoft.Json.Serialization.JsonContainerContract containerContract， Newtonsoft.Json.Serialization.JsonProperty containerMember，System.Object existingValue）[0x00000] in：0 at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize（Newtonsoft.Json.JsonReader reader，System.Type objectType，Boolean checkAdditionalContent）[0x00000] in：0
JSON：
{
"body": {
"devices": [
{
"_id": "XXX",
"cipher_id": "enc:16:XXX",
"last_status_store": 1483489982,
"modules": [
{
"_id": "XXX",
"type": "NAModule1",
"last_message": 1483489978,
"last_seen": 1483489933,
"dashboard_data": {
"time_utc": 1483489933,
"Temperature": -0.2,
"temp_trend": "stable",
"Humidity": 89,
"date_max_temp": 1483489933,
"date_min_temp": 1483484498,
"min_temp": -0.4,
"max_temp": -0.2
},
"data_type": [
"Temperature",
"Humidity"
],
"module_name": "Außen",
"last_setup": 1384606905,
"battery_vp": 5870,
"battery_percent": 95,
"rf_status": 81,
"firmware": 43
},
{
"_id": "XXXX",
"type": "NAModule4",
"last_message": 1483489978,
"last_seen": 1483489933,
"dashboard_data": {
"time_utc": 1483489933,
"Temperature": 21.7,
"temp_trend": "stable",
"Humidity": 38,
"CO2": 1139,
"date_max_temp": 1483489933,
"date_min_temp": 1483485422,
"min_temp": 21.5,
"max_temp": 21.7
},
"data_type": [
"Temperature",
"CO2",
"Humidity"
],
"module_name": "Schlafzimmer",
"last_setup": 1414704430,
"battery_vp": 4876,
"battery_percent": 38,
"rf_status": 79,
"firmware": 43
}
],
"place": {
"altitude": 210,
"city": "XXX",
"country": "DE",
"timezone": "Europe/XXX",
"location": [
3.12345675665,
12.12345667899
]
},
"station_name": "XXX",
"type": "NAMain",
"dashboard_data": {
"AbsolutePressure": 993.7,
"time_utc": 1483489969,
"Noise": 51,
"Temperature": 21.8,
"temp_trend": "stable",
"Humidity": 44,
"Pressure": 1021.2,
"pressure_trend": "down",
"CO2": 1069,
"date_max_temp": 1483484530,
"date_min_temp": 1483485740,
"min_temp": 21.6,
"max_temp": 21.8
},
"data_type": [
"Temperature",
"CO2",
"Humidity",
"Noise",
"Pressure"
],
"co2_calibrating": false,
"date_setup": 1384607020,
"last_setup": 1384607020,
"module_name": "Wohnzimmer",
"firmware": 102,
"last_upgrade": 1440006125,
"wifi_status": 62,
"friend_users": [
"XXXX"
]
}
],
"user": {
"mail": "XXX@XXX.XXX",
"administrative": {
"country": "DE",
"reg_locale": "de-DE",
"lang": "de-DE",
"unit": 0,
"windunit": 0,
"pressureunit": 0,
"feel_like_algo": 0
}
}
},
"status": "ok",
"time_exec": 0.050105810165405,
"time_server": 1483490016
}
在Windows中它可以正常工作。
答案 0 :(得分：3)
我没有raspbian来测试，但是从追溯中，似乎JsonTextReader.ParseNumber()可能正在解析数字＆＃39; -0.2＆＃39;在一个特定于语言环境的文化中（你是用德语运行，也许是？）尽管明确尝试使用不变文化来解析数字，如source code所示：
double value;
if (!double.TryParse(number, NumberStyles.Float, CultureInfo.InvariantCulture, out value))
{
throw ThrowReaderError("Input string '{0}' is not a valid number.".FormatWith(CultureInfo.InvariantCulture, _stringReference.ToString()));
}
可能你正在使用分叉版本的Json.NET，或者可能在Raspbian上有一些Mono bug，但无论哪种方式错误的文化似乎都被使用了。
作为一种解决方法，您可以尝试暂时将当前文化设置为不变文化：
Dim opts = New Newtonsoft.Json.JsonSerializerSettings() With { _
.FloatParseHandling = Newtonsoft.Json.FloatParseHandling.Double _
}
Dim myJSON as Newtonsoft.Json.Linq.JObject
Dim oldCulture = Thread.CurrentThread.CurrentCulture
Try
Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture
myJSON = Newtonsoft.Json.JsonConvert.DeserializeObject(Of Newtonsoft.Json.Linq.JObject)(myStationJSON, opts)
Finally
Thread.CurrentThread.CurrentCulture = oldCulture
End Try
并且，如果这不起作用，请尝试使用LANG=en_US.UTF-8运行您的exe，如here所述，这似乎描述了类似的问题。