Convert the model's fields as Dictionary in another model's field

I have this model:

namespace SomeApp.Models
{
    public class FirstModel
    {
        public int uid { get; set; }
        public string? id { get; set; }
        public string? firstname { get; set; }
        public string? lastname { get; set; }
     }
}

whose fields I need to convert to a dictionary or JSON object in another model. I'm using the GetFields Method.

namespace SomeApp.Models
{
    public class SecondModel
    {
        // other fields


        public Dictionary<string, string> FirstModelTransfer { get; set; }

        public void SetFirstModelTransfer(FirstModel firstModel)
        {
            FieldInfo[] firstModelFields = typeof(FirstModel).GetFields();

            Dictionary<string, string> dict = new();

            foreach (var firstModelField in firstModelFields)
            {
                string fieldName = firstModelField.Name;
                string fieldValue = firstModelField.GetValue(fieldName).ToString();

                dict[fieldName] = fieldValue;
            }

            FirstModelTransfer = dict;
        }
    }
}

I want the result to look like

{
  // other fields
  "FirstModelTransfer": {
    "firstname": "Sample firstname",
    "lastname": "Sample lastname"
  }
}

But currently, it looks like this,

{
  // other fields
  "FirstModelTransfer": {
    "additionalProp1": "string",
    "additionalProp2": "string",
    "additionalProp3": "string"
  }
}

I don't know if this matters but:

services.AddDbContext<SecondModelsContext>();
services.AddDbContext<FirsModelsContext>();

This is the ordering of the dbContexts in which each model was registered.

From your code, you are trying to get the properties but not fields in FirstModel class.

Thus, you should get the properties as PropertyInfo[] via GetProperties().

PropertyInfo[] firstModelFields = typeof(FirstModel).GetProperties();

To get the property value via Reflection, you have to pass the object instance as mentioned in PropertyInfo.GetValue(Object) method.

string fieldValue = firstModelField.GetValue(firstModel)?.ToString();

Alternatively, you may use the Newtonsoft.Json library to convert an object into a Dictionary<string, string> instance without Reflection.

using Newtonsoft.Json.Linq;

dict = JObject.FromObject(firstModel)
	.ToObject<Dictionary<string, string>>();