Why is the string's parameter null in axios?

Question

I send a parameter in axios to api and I run linq to get the result.

Unfortunately when it comes to a function in api I get the value null

Where am I wrong?

the code:

react:
 const code= "sdasdasdadad"
        axios.post('api/UserDetails/', code).then((response) => setUserDetails(response.data));

C#:
   [Microsoft.AspNetCore.Mvc.Route("UserDetails")]
        [Microsoft.AspNetCore.Mvc.HttpPost]
        public Users UserDetails(string code)
        {
            
            try
            {

                return _context.User.Where(x=>x.Code==code).FirstOrDefault();



            }
            catch (Exception)
            {
                return null;

            }
        }

Answer 1

If you really want your APIs work well with plain text input, you can try to implement a custom plain text input formatter, like below.

public class TextPlainInputFormatter : TextInputFormatter
{
    public TextPlainInputFormatter()
    {
        SupportedMediaTypes.Add("text/plain");
        SupportedEncodings.Add(UTF8EncodingWithoutBOM);
        SupportedEncodings.Add(UTF16EncodingLittleEndian);
    }

    protected override bool CanReadType(Type type)
    {
        return type == typeof(string);
    }

    public override async Task<InputFormatterResult> ReadRequestBodyAsync(InputFormatterContext context, Encoding encoding)
    {
        string data = null;
        using (var streamReader = new StreamReader(context.HttpContext.Request.Body))
        {
            data = await streamReader.ReadToEndAsync();
        }
        return InputFormatterResult.Success(data);
    }
}

Configure and use custom formatter

services.AddControllers(opt => opt.InputFormatters.Insert(0, new TextPlainInputFormatter()));

API Action

[Microsoft.AspNetCore.Mvc.Route("UserDetails")]
[Microsoft.AspNetCore.Mvc.HttpPost]
public Users UserDetails([FromBody]string code)
{

    //...

Make request using axios

const code = "sdasdasdadad";

const headers = {
    'Content-Type': 'text/plain'
};

axios.post('api/UserDetails', code, { headers: headers }).then((response) => setUserDetails(response.data));

Test Result