ASP.NET Core. Approach 1
If your Controller extends ControllerBase or Controller you can use Content(...) method:
[HttpGet]
public ContentResult Index()
{
return base.Content("<div>Hello</div>", "text/html");
}
ASP.NET Core. Approach 2
If you choose not to extend from Controller classes, you can create new ContentResult:
[HttpGet]
public ContentResult Index()
{
return new ContentResult
{
ContentType = "text/html",
Content = "<div>Hello World</div>"
};
}
Legacy ASP.NET MVC Web API
Return string content with media type text/html:
public HttpResponseMessage Get()
{
var response = new HttpResponseMessage();
response.Content = new StringContent("<div>Hello World</div>");
response.Content.Headers.ContentType = new MediaTypeHeaderValue("text/html");
return response;
}