Reputation: 21
I don't know if there is an existing name for that case, but I'm trying to retrieve data from NASA API (https://api.nasa.gov/) and I have a simple challenge to catch a list of objects near earth. Here is the JSON response I have from the GET request I do to "https://api.nasa.gov/neo/rest/v1/feed?...."
{
"links": {
"next": "http://www.neowsapp.com/rest/v1/feed?start_date=2021-07-04&end_date=2021-07-04&detailed=false&api_key=NjgpxgSbYHXyFSBI3HaOhRowtjMZgAKv2t4DMRym",
"prev": "http://www.neowsapp.com/rest/v1/feed?start_date=2021-07-02&end_date=2021-07-02&detailed=false&api_key=NjgpxgSbYHXyFSBI3HaOhRowtjMZgAKv2t4DMRym",
"self": "http://www.neowsapp.com/rest/v1/feed?start_date=2021-07-03&end_date=2021-07-03&detailed=false&api_key=NjgpxgSbYHXyFSBI3HaOhRowtjMZgAKv2t4DMRym"
},
"element_count": 6,
"near_earth_objects": {
"2021-07-03": [
{
"links": {
"self": "http://www.neowsapp.com/rest/v1/neo/3701710?api_key=NjgpxgSbYHXyFSBI3HaOhRowtjMZgAKv2t4DMRym"
},
"id": "3701710",
"neo_reference_id": "3701710",
"name": "(2014 WF497)",
"nasa_jpl_url": "http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3701710",
"absolute_magnitude_h": 20.23,
"estimated_diameter": {
"kilometers": {
}
And that's the way it is built in Visual Studio (using the Special Paste option for JSON)
public class NearEarthObject
{
public Links links { get; set; }
public int element_count { get; set; }
public Near_Earth_Objects near_earth_objects { get; set; }
}
public class Links
{
public string next { get; set; }
public string prev { get; set; }
public string self { get; set; }
}
public class Near_Earth_Objects
{
public _20210703[] _20210703 { get; set; }
}
public class _20210703
{
public Links1 links { get; set; }
public string id { get; set; }
public string neo_reference_id { get; set; }
public string name { get; set; }
public string nasa_jpl_url { get; set; }
public float absolute_magnitude_h { get; set; }
public Estimated_Diameter estimated_diameter { get; set; }
public bool is_potentially_hazardous_asteroid { get; set; }
public Close_Approach_Data[] close_approach_data { get; set; }
public bool is_sentry_object { get; set; }
}
The question is, inside of the element "near_earth_objects", there is an element called "2021-07-03" (the date of the data I requested), the problem is that I am trying to include it into a DataGridView made in .NET C# (Windows Forms, but that doesn't matters here, I think) and the user wants to get the information by date. So, "2021-07-03" is a valid member just for one day, and the user should be able to get data from multiple days.
So, is there a way in C# to get all child objects inside of near_earth_objects without knowing their names since there will be the option to search for asteroids from date X to Y in my application?
Upvotes: 1
Views: 326
Reputation: 522
Using System.Text.Json
The API response will map to the following classes
public class Neo
{
public Links Links { get; set; }
public int ElementCount { get; set; }
public Dictionary<string, List<NearEarthObject>> NearEarthObjects { get; set; }
}
public class Links
{
public string Next { get; set; }
public string Prev { get; set; }
public string Self { get; set; }
}
public class NearEarthObject
{
public Links Links { get; set; }
public string Id { get; set; }
public string Name { get; set; }
// Other properties
}
The NearEarthObjects
is simply a Dictionary
, where the key is the formatted date and value is a List
containing NearEarthObject
The PropertyNamingPolicy will allow us to support the API's underscore property naming convention.
public class UnderscoreNamingPolicy : JsonNamingPolicy
{
public override string ConvertName(string name)
{
return name.Underscore();
}
}
Example usage
// using using System.Text.Json;
var response = await new HttpClient().GetStringAsync(url);
var neo = JsonSerializer.Deserialize<Neo>(response, new JsonSerializerOptions
{
PropertyNamingPolicy = new UnderscoreNamingPolicy()
});
foreach(var neos in neo.NearEarthObjects)
{
Console.WriteLine(neos.Key);
}
Upvotes: 2
Reputation: 71
use System.Text.Json
, JsonNamingPolicy
demo code
public class DynamicNamePolicy : JsonNamingPolicy
{
public override string ConvertName(string name)
{
var today = DateTime.Today.ToString("yyyy-MM-dd");
if (name.Equals("DateData")) //model property name
return today; //convert to json string property name
return name;
}
}
//data deserialize
string data = ""; //json string
var obj = JsonSerializer.Deserialize<NearEarthObject>(data, new JsonSerializerOptions
{
PropertyNamingPolicy = new DynamicNamePolicy(),
});
Upvotes: 1