Add a field into JSON array

问题

I got a JSON string with an array like this:

 {
  "Id": 123,
  "Username": "Sr. X",
  "Packages": [
    {
      "Name": "Cups",
      "SupplierId": 1,
      "ProviderGroupId": 575,
      "SupplierName": "Foo Cups"
    },
    {
      "Name": "Pins",
      "SupplierId": 5,
      "ProviderGroupId": 1082,
      "SupplierName": "Foo Pins"
    }
  ]
}

and I want to add a new field into Packages array like:

"Packages": [
    {
      "Name": "Cups",
      "SupplierId": 1,
      "ProviderGroupId": 575,
      "SupplierName": "Foo Cups",
      "New Field": "Value"
    },...

Right now I can add a new field but in the main object, I'm using Json.NET library to do the job, but it seems that the documentation doesn't reach that level.

Have any one of you done it before?

回答1:

JObject implemets IDictionary.

var jObj = JObject.Parse(json);
foreach(var item in jObj["Packages"])
{
    item["New Field"] = "Value";
}
var newjson = jObj.ToString(Newtonsoft.Json.Formatting.Indented);

回答2:

Try

JObject root = (JObject) JsonConvert.DeserializeObject(File.ReadAllText("products.json"));
JArray packages = (JArray) root["Packages"];

JObject newItem = new JObject();
newItem["Name"] = "Cups";
// ...

packages.Add(newItem);

Console.WriteLine(root); // Prints new json

来源：https://stackoverflow.com/questions/39416530/add-a-field-into-json-array