Add JObject to another JObject in .NET

Question

I have two JObject's loaded from the following two JSON files:

{
  "data": {
    "organism": {
      "human": [
        {
          "firstName": "John",
          "lastName": "Doe"
        }
      ]
    }
  }
}

{
  "degrees": [
    {
      "type": "bachelor",
      "major": "Math"
    },
    {
      "type": "master",
      "major": "Computer Science"
    }
  ]
}

I want to combine them into one JObject like this:

{
  "data": {
    "organism": {
      "human": [
        {
          "firstName": "John",
          "lastName": "Doe",
          "degrees": [
            {
              "type": "bachelor",
              "major": "Math"
            },
            {
              "type": "master",
              "major": "Computer Science"
            }
          ]
        }
      ]
    }
  }
}

I have tried to add them as new field like this, but I am getting an error that i can't add JObject to another JObject:

jObject1["data"]["organism"]["human"][0]["lastName"].Parent.AddAfterSelf(jObject2)

I then tried to add it using JProperty but it just added a duplicate field which is not the format I need.

jObject1["data"]["organism"]["human"][0]["lastName"].Parent.AddAfterSelf(new JProperty("degrees",jobject2))

I am not sure how to proceed from this.

score 2 · Answer 1 · answered Nov 18 '19 at 23:40

You can do this as follows:

((JObject)jObject1["data"]["organism"]["human"][0]).Add(jObject2.Property("degrees"));

Notes:

Casting the return of jObject1["data"]["organism"]["human"][0] to JObject ensures there really is a JSON object at that path. Assuming the cast can be made, properties can be added easily.
Your query adds an additional term ["lastName"], which essentially selects the JValue "Doe" corresponding to "lastName": "Doe". Not sure why you are doing that, so I removed it from my solution.
JObject.Property returns the JProperty with the given name, or null if not found. That JProperty can then be added to another JObject via its Add() method. Note that, in fact, a clone of the selected property is added, see this answer to JArray.Remove(JToken) does not delete for why.

Demo fiddle here.

Add JObject to another JObject in .NET

1 Answers1