Build JObject from JSONPath

问题

I'm a bit new to using the Newtonsoft JSON library for .NET. Is there any way to create a JObject or JToken from a JSONPath?

So for example something like the following.

string jsonPath = "$.ArrayA[0].ArrayB[0].Property";
JObject jObj = JObject.FromJSONPath(jsonPath); // SOMETHING LIKE THIS

The result would be a JObject or JToken that looks like this.

{
    "ArrayA": [{
        "ArrayB": [{
            "Property": ""
        }]
    }
}

回答1:

No.

If you have some existing JSON, you can parse it to a JToken and then select one or more descendant JTokens from it using SelectToken or SelectTokens with a JsonPath expression. For example:

string json = @"{ ""ArrayA"": [{ ""ArrayB"": [{ ""Property"": ""foo"" }] }] }";
JToken token = JToken.Parse(json);
JToken fooToken = token.SelectToken("$..Property");
Console.WriteLine(fooToken.ToString());    // prints "foo"

You can also manually build a nested structure of JTokens. For example, you can create the JObject in your question like this:

var obj = new JObject(new JProperty("ArrayA", new JArray(
             new JObject(new JProperty("ArrayB", new JArray(
                new JObject(new JProperty("Property", ""))))))));

However, there is no built-in way to create a JToken from nothing but a JsonPath expression. You would need to roll your own method to do something like that. But keep in mind that JsonPath was designed as a query mechanism; it doesn't map cleanly to creation of new objects. Here are some issues you would need to think about:

In your example expression, $.ArrayA[0].ArrayB[0].Property, what type is Property? Is it string, number, boolean, object or an empty array? How would you specify that?
How would you specify creation of an object with multiple properties?
What would an expression like $..book[(@.length-1)] create?

来源：https://stackoverflow.com/questions/43988405/build-jobject-from-jsonpath

标签

json.net