Activity: Implementing Your Own IActionResult

Scenario

You want to learn how to access the underlying stream of response of a string.

Aim

Write an activity result that would capitalize the given string.

Steps for completion

First, add the following class to your projects:

Go to https://goo.gl/GDi6JS to access the code.

public class UpperStringActionResult : ActionResult
{
  readonly string str;
  public UpperStringActionResult(string str)
  {
    this.str = str;
  }
  public override void ExecuteResult(ActionContext context)
  {
    var upperStringBytes =
    Encoding.UTF8.GetBytes(str.ToUpper());
    context.HttpContext.Response.Body.Write(
    upperStringBytes, 0, upperStringBytes.Length);
  }
}

What is encoding? Encoding is basically a process in which a sequence of characters is put into a specialized format. The characters could be numerical, alphabet, symbols, and so on. The purpose is to serve efficient transmission and storage. What is UTF-8? UTF-8 is the encoding for the web for efficiency reasons.

Then, revise your controller action, as follows:

Go to https://goo.gl/DTWzN4 to access the code.

public IActionResult IndexUpper()
{
  return new UpperStringActionResult("Hello World! I am learning MVC!");
}

Then, run your application. You'll get the following output:

As you can see, all letters are in capitals.