Return HTML from ASP.NET Web API

145
votes

How to return HTML from ASP.NET MVC Web API controller?

I tried the code below but got compile error since Response.Write is not defined:

public class MyController : ApiController
{
    [HttpPost]
    public HttpResponseMessage Post()
    {
        Response.Write("<p>Test</p>");
        return Request.CreateResponse(HttpStatusCode.OK);
    }
 }
2
c#htmlasp.net-mvcasp.net-mvc-4asp.net-web-api
Why are you using WebAPI if you want to return HTML? I mean this is what ASP.NET MVC and ASP.NET WebForms are for. – Stilgar
Thank you, excellent. I changed controller to regular controller. – Andrus
@Stilgar One reason could have been that he does not use the MVC stack, neither any rendering engine but still want to provide a server facade to some Html. A use case can be that you have a Web Api that give some Html with a client side templating engine that will render everything in a later stage. – Patrick Desjardins
@Stilgar Another use case I encountered is returning an html page to provide feedback for an account creation confirmation, when the user clicks on the link you provide through email – wiwi

2 Answers

296
votes

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;
}
59
votes

Starting with AspNetCore 2.0, it's recommended to use ContentResult instead of the Produce attribute in this case. See: https://github.com/aspnet/Mvc/issues/6657#issuecomment-322586885

This doesn't rely on serialization nor on content negotiation.

[HttpGet]
public ContentResult Index() {
    return new ContentResult {
        ContentType = "text/html",
        StatusCode = (int)HttpStatusCode.OK,
        Content = "<html><body>Hello World</body></html>"
    };
}