Return HTML from ASP.NET Web API

c# html asp.net-mvc asp.net-mvc-4 asp.net-web-api

146,549

Solution 1

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;
}

Solution 2

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>"
    };
}

146,549

Andrus

Updated on July 08, 2022

Comments

Andrus almost 2 years
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);
    }
 }
```
- Stilgar over 9 years
  
  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.
- Andrus over 9 years
  
  Thank you, excellent. I changed controller to regular controller.
- Patrick Desjardins over 9 years
  
  @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.
- wiwi almost 7 years
  
  @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
Parshuram Kalvikatte over 7 years

Its not supporting in ASP.NET MVC Core HttpResponseMessage
Andrei over 7 years

@Parshuram I've just checked your statement. I can use HttpResponseMessage in ASP.NET Core. It is located under System.Net.Http.
Parshuram Kalvikatte over 7 years

ohk thanks but now MediaTypeHeaderValue not supporting
guyfromfargo over 6 years

When I do this using ASP.NET MVC 5 I get the response. I don't get any of the HTML content back. All I receive is "StatusCode: 200, ReasonPhrase: 'OK', Version: 1.1, Content: System.Net.Http.StringContent, Headers: { Content-Type: text/html }"
Andrei over 6 years

@guyfromfargo have you tried [Produces] approach?
philw over 6 years

I could not get the "produces" answer to work at all on 2.0, this however works fine.
Pavel Samoylenko about 6 years

If you want to show a html from file, just add "var content = System.IO.File.ReadAllText("index.html");"
James Scott about 6 years

Yup, if you are using ASP.NET Core 2.0 this is the way to go!
Jose Manuel Ojeda almost 6 years

for me the code above works perfect on my local iis express but in normal iis it throws an exception that can serialize the response Type 'System.Net.Http.StringContent' cannot be serialized. Consider marking it with the DataContractAttribute attribute, and marking all of its members you want serialized with the DataMemberAttribute attribute. If the type is a collection, consider marking it with the CollectionDataContractAttribute. See the Microsoft .NET Framework documentation for other supported types.
Lingam about 4 years

What if the HTML file is in the local directory and it also has css, js linked. How do we serve the file then?
carlin.scott almost 4 years

For Razor Pages, you can call the PageModel Content() method instead of creating ContentResult directly. I'm not sure if this is available for Controllers as well.