TJSON.JsonToObject<classname> not working in Delphi - json

Question

I am trying to convert Json trying to class object, but the values are not appearing in the new object variable. The resulting object has blank value in string and 0 in integer.
Thanks in advance.
Code:
type
Student =class
public
Name : string;
Age : Integer;
end;
procedure TForm2.Button5Click(Sender: TObject);
var
Student1, Student2: Student;
STR: string;
begin
Student1 := Student.Create;
Student2 := Student.Create;
try
Student1.Name := 'Sam';
Student1.Age := 24;
str := TJson.ObjectToJsonString(Student1);
Form2.outputMemo.Lines.Add(str);
Student2 := TJSON.JsonToObject<Student>(str);
Form2.outputMemo.Lines.Add(Student2.Name);
Form2.outputMemo.Lines.Add(Student2.Age.ToString);
finally
Student1.Free;
Student2.Free;
end;
//Form2.outputMemo.Lines.Text :=TJson.ObjectToJsonObject(Student1);
end;
Output:
{"name":"Sam","age":24}
0
Edit:
I just saw this, and it worked when I changed the names to FName and FAge... what a sorcery!, can anyone please explain the logic behind this?
Delphi Rest.JSON JsonToObject only works with f variables

Answer 1

The internal mapping of JSON fields to Delphi fields is prefixing them with F and changing the following character to upper case. If you want complete control over this you can specify the JSON name with an attribute:
type
Student =class
public
[JSONName('name')]
Name : string;
[JSONName('age')]
Age : Integer;
end;
Note that the JSON names given are case sensitive.
You need to include REST.Json.Types to the uses so that the attribute declaration can be found.