System.Text.Json.JsonException - Error deserializing - asp.net-core

Question

Here is my code:
public class Element
{
public string? Group { get; set; }
public int Position { get; set; }
public string? Name { get; set; }
public int Number { get; set; }
[JsonPropertyName("small")]
public string? Sign { get; set; }
public double Molar { get; set; }
public IList<int>? Electrons { get; set; }
public override string ToString()
{
return $"{Sign} - {Name}";
}
}
public List<Element> LoadJson()
{
using (StreamReader r = new StreamReader("jsondata/elements.json"))
{
string json = r.ReadToEnd();
var ElementObject = JsonSerializer.Deserialize<List<Element>>(json);
return ElementObject;
}
}
elements.json
{
"elements": [
{
"group": "Other",
"position": 0,
"name": "Hydrogen",
"number": 1,
"small": "H",
"molar": 1.00794,
"electrons": [
1
]
},
{
"group": "Noble Gas (p)",
"position": 17,
"name": "Helium",
"number": 2,
"small": "He",
"molar": 4.002602,
"electrons": [
2
]
}
]
}
while I am trying to deserialize I get
System.Text.Json.JsonException: 'The JSON value could not be converted to System.Collections.Generic.List`1[BlazorApp4.Shared.Entities.Element]. Path: $ | LineNumber: 0 |
What am I missing?

Answer 1

The JSON doesn't represent a List<Element>. It represents an object which has a property which is a List<Element>.
Create that object:
public class Root
{
public List<Element> Elements { get; set; }
}
And deserialize into that:
var root = JsonSerializer.Deserialize<Root>(json);
return root.Elements;