Creating Route Constraints using Attribute-based Routing in ASP.NET Web API

When you are writing your Web API methods, you may encounter a situation whereby you have two different methods that need to be distinguished from each other through their routes?

For example, if you have a method GetById(int id) and GetById(string id), how do you distinguish between these 2 routes when documenting your Web API using Attribute-based routing?

Well, through Route Constraints of course!

https://www.asp.net/web-api/overview/web-api-routing-and-actions/attribute-routing-in-web-api-2#constraints

Therefore, you can then have Web API methods like the following:

	[Route("{id:int}")]
	[HttpGet]
	public IHttpActionResult GetById(int id)
	{
	try
	{
	return Ok(_myRepository.GetById(id));
	}
	catch (Exception ex)
	{
	return BadRequest(ex.UnwrapInnerExceptionMessages());
	}
	}
	[Route("{id}")]
	[HttpGet]
	public IHttpActionResult GetById(string id)
	{
	try
	{
	return Ok(_myRepository.GetById(id));
	}
	catch (Exception ex)
	{
	return BadRequest(ex.UnwrapInnerExceptionMessages());
	}
	}

view raw ASPNETWebAPIRouteConstraints.cs hosted with ❤ by GitHub