Why we need IEnumerable<string> before get method?

Question

I just started learning web API using ASP.NET. I created a new project from visual studio and trying to understand MVC folder structure and API calls.

Here what I want to know is: why do we need IEnumerable<string> before the get method.

In myValuesController.cs,

        // GET api/values
        public IEnumerable<string> Get()
        {
            return new string[] { "value1", "value2" };
        }

According to the Microsoft Documentation, this exposes the enumerator, which supports a simple iteration over a collection of a specified type but think if I have an integer in my database do I need to convert it into string as well?

Answer 1

In addition, you can return IHttpActionResult with string values:

public IHttpActionResult Get()
{
    var model = new string[] { "value1", "value2" };
    return Ok(model);
}

or with int values:

public IHttpActionResult Get()
{
    var model = new int[] { 1, 2, 3 };
    return Ok(model);
}

IHttpActionResult allows you to return HTTP statuses and more. Here are some advantages of using the IHttpActionResult interface:

• Simplifies unit testing your controllers.
• Moves common logic for creating HTTP responses into separate classes.
• Makes the intent of the controller action clearer, by hiding the low-level details of constructing the response.

Answer 2

If your GET-endpoint should return a collection of numbers instead of a single number, you surely need to return some kind of list, be it IEnumerable or List or whatever.