Bind query parameters to a model in ASP.NET Core

Question

I am trying to use model binding from query parameters to an object for searching.

My search object is

[DataContract] public class Criteria  {   [DataMember(Name = "first_name")]   public string FirstName { get; set; } } 

My controller has the following action

[Route("users")] public class UserController : Controller  {   [HttpGet("search")]   public IActionResult Search([FromQuery] Criteria criteria)   {     ...   } } 

When I call the endpoint as follows .../users/search?first_name=dave the criteria property on the controller action is null. However, I can call the endpoint not as snake case .../users/search?firstName=dave and the criteria property contains the property value. In this case Model Binding has worked but not when I use snake_case.

How can I use snake_case with Model Binding?

Answer 1

You need to add [FromQuery] attribute to the model properties individually

public class Criteria {   [FromQuery(Name = "first_name")]   public string FirstName { get; set; } } 

Answer 2

Solution for .net core 2.1, 2.2, 3.0 and 3.1

Or without attributes you can do something like this which is cleaner I think (of course if the model properties are same as query parameters).

Meanwhile I use it in .net core 2.1, 2.2 and 3.0 preview & 3.1.

public async Task<IActionResult> Get([FromQuery]ReportQueryModel queryModel)  {   }