Query parameter routing with asp .net core

Question

I'd like to use url query parameter instead of path parameter using .net core API.

controller

[Route("api/[controller]/[action]")]
public class TranslateController : Controller
{
    [HttpGet("{languageCode}")]
    public IActionResult GetAllTranslations(string languageCode)
    {
        return languageCode;
    }
}

startup.cs is using only default settings

public void ConfigureServices(IServiceCollection services)
{
    // Add framework services.
    services.AddMvc()
            .AddJsonOptions(jsonOptions =>
            {
                jsonOptions.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore;
                jsonOptions.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
                jsonOptions.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
            });

    services.AddLogging();
    services.AddSingleton<IConfiguration>(Configuration);

    services.AddSwaggerGen(c =>
    {
        c.SingleApiVersion(new Info
        {
            Version = "v1",
            Title = "Translate API",
            Description = "bla bla bla description",
            TermsOfService = "bla bla bla terms of service"
        });
    });
}

// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    loggerFactory.AddConsole(Configuration.GetSection("Logging"));
    loggerFactory.AddDebug();

    app.UseMvc();

    app.UseSwagger();
    app.UseSwaggerUi();
}

my swagger request looks like this

my postman request is here

I would like to change my GetAllTranslations to accept query parameter instead of path parameter but when I change my postman query to

http://localhost:42677/api/Translate/GetAllTranslations?languageCode=en

I will get error 404 Not found so obviously my controller path is not set correctly, but I cannot find out how to do this... Any Ideas?

I have tried removing the [HttpGet("{languageCode}")] attribute, but I keep getting null parameter instead of the value.

Answer 1

This is what you're looking for

public IActionResult GetAllTranslations([FromQuery]string languageCode)

Answer 2

The answer from @jcmontx worked, but it doesn't explain why parameter bindind needs to be explicitly set. I am still not sure if and why is this enforced, but one reason would be that if binding parameters are not set explicitly, it opens up the API to be used the way it was not intended, which is not very secure neither a good practice.