WebApi 属性路由不适用于 [FromUri]

Question

I have a webapi method as shown below

[HttpGet]
[Route("students")]
public string Get([FromUri]Student student)
{
    return "value";
}

and my webapiconfig is

    config.MapHttpAttributeRoutes();

    config.Routes.MapHttpRoute(
        name: "DefaultApi",
        routeTemplate: "api/{controller}/{id}",
        defaults: new { id = RouteParameter.Optional }
    );

When i dont use the [Route("..")] attribute then i get the student object populated and it is null if i use [Route("..")].

Can anyone please help how to solve this.

Thanks

Answer 1

When you use [Route("students")] the following URL will match http://localhost/students?Name=name&Age=12 assuming your Student class has Name and Age properties.

When you don't provide any query parameter it will be null and it's expected behavior.

If you Student object is a struct it will be required parameter, so you will get exception from WebApi, not null

Answer 2

simply, check if its null

[HttpGet]
[Route("students")]
public string Get([FromUri] Student student)
{
    if (student == null)
        student = new Student();
    return "value";
}