C# 10 / .NET 6 / System.Text.Json
I'm working with an API that returns as JSON response. I'm trying to use System.Text.Json
to deserialize the JSON response into a class. I'm receiving a JsonException and could use help understanding what I'm doing wrong.
I call the API and store the JSON response:
string json = await Retreive.Fetch(target);
Here's the output of Console.WriteLine(json)
:
[{"id": 1148082,"name": "TestGroup","group_type":"console_group","provisioning_guid": null,"member_count": 1,"current_risk_score": 36.3,"status": "active"},{"id": 1148788,"name": "Group2","group_type": "smart_group","provisioning_guid": null,"member_count": 9,"current_risk_score": 39.7,"status": "active"},{"id": 1148792,"name": "Group3","group_type": "smart_group","provisioning_guid": null,"member_count": 9,"current_risk_score": 39.7,"status": "active"}]
Here's a pretty-printed version if it helps:
[
{
"id": 1148082,
"name": "TestGroup",
"group_type": "console_group",
"provisioning_guid": null,
"member_count": 1,
"current_risk_score": 36.3,
"status": "active"
},
{
"id": 1148788,
"name": "Group2",
"group_type": "smart_group",
"provisioning_guid": null,
"member_count": 9,
"current_risk_score": 39.7,
"status": "active"
},
{
"id": 1148792,
"name": "Group3",
"group_type": "smart_group",
"provisioning_guid": null,
"member_count": 9,
"current_risk_score": 39.7,
"status": "active"
}
]
Using Visual Studio 2022's Paste JSON As Classes function, I get the following class structure:
public class Rootobject
{
public Class1[] Property1 { get; set; }
}
public class Class1
{
public int id { get; set; }
public string name { get; set; }
public string group_type { get; set; }
public object provisioning_guid { get; set; }
public int member_count { get; set; }
public float current_risk_score { get; set; }
public string status { get; set; }
}
I'm trying: Rootobject? gag = JsonSerializer.Deserialize<Rootobject>(json);
A JsonException is thrown:
Unhandled exception. System.Text.Json.JsonException: The JSON value could not be converted to KB4.Rootobject. Path: $ | LineNumber: 0 | BytePositionInLine: 1. at System.Text.Json.ThrowHelper.ThrowJsonException_DeserializeUnableToConvertValue(Type propertyType) at System.Text.Json.Serialization.Converters.ObjectDefaultConverter
1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value) at System.Text.Json.Serialization.JsonConverter
1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value) at System.Text.Json.Serialization.JsonConverter1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state) at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan
1 utf8Json, JsonTypeInfo jsonTypeInfo, Nullable1 actualByteCount) at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan
1 json, JsonTypeInfo jsonTypeInfo) at System.Text.Json.JsonSerializer.Deserialize[TValue](String json, JsonSerializerOptions options) at KB4.Kb4.Main() in C:<REDACTED>\Program.cs:line 188 at KB4.Kb4.()
Some things I have tried:
- Changing the name of the
Rootobject
class toGetAllGroups
- Thinking the JSON may be somehow malformed in the response, I pasted it into a text file and load the JSON from there and then attempt deserialization again.
- Reviewed Deserialize a JSON array in C# but that's using JavaScriptSerializer.
Neither of the above produces a different result.
What am I doing wrong?
CodePudding user response:
your Rootobject class would be working if your json starts with this
{ "property1": [{"id": 1148082,"name": .....] }
and the array had a property name. but your json don't have property1, so you should start to deserialize json array directly
Class1[] result = System.Text.Json.JsonSerializer.Deserialize<Class1[]>(json);