Agfdhyk

I am using ASP.NET 5. I need to convert IHtmlContent to String

IIHtmlContent is part of the ASP.NET 5 Microsoft.AspNet.Html.Abstractions namespace and is an interface that TagBuilder implements

Simplified I have the following method

public static IHtmlContent GetContent()

{

    return new HtmlString("<tag>blah</tag>");

}

When I reference it

string output = GetContent().ToString();

I get the following output for GetContent()

"Microsoft.AspNet.Mvc.Rendering.TagBuilder" 

and not

<tag>blah</tag>

which I want

I also tried using StringBuilder

StringBuilder html = new StringBuilder();

html.Append(GetContent());

but it also appends the same namespace and not the string value

I tried to cast it to TagBuilder

TagBuilder content = (TagBuilder)GetContent();

but TagBuilder doesn't have a method that converts to string

How do I convert IHtmlContent or TagBuilder to a string?

If all you need to do is output the contents as a string, just add this method and pass your IHtmlContent object as a parameter to get the string output:

public static string GetString(IHtmlContent content)

{

    var writer = new System.IO.StringWriter();

    content.WriteTo(writer, HtmlEncoder.Default);

    return writer.ToString();

}

You may want to reconsider why you're taking this approach as the TagBuilder allows for just about any type of custom HTML you can think of. Outputting the text manually probably isn't necessary.

Adding to the answer above:

The new instance of the HtmlEncoder doesn't work in ASP.NET Core RTM as the Microsoft.Extensions.WebEncoders namespace was removed and the new HtmlEncoder class is moved to a new namespace System.Text.Encodings.Web, but this class is now written as an abstract and sealed class so you can't create a new instance or a derived class from it.

Pass HtmlEncoder.Default to the method and it will work

public static string GetString(IHtmlContent content)

{

    var writer = new System.IO.StringWriter();

    content.WriteTo(writer, HtmlEncoder.Default);

    return writer.ToString();

}

ASP.NET Core actually introduced handful of careful optimizations. If you are building an HTML extension method, then the most efficient way is to avoid string:

public static IHtmlContent GetContent(this IHtmlHelper helper)

{

    var content = new HtmlContentBuilder()

                     .AppendHtml("<ol class='content-body'><li>")

                     .AppendHtml(helper.ActionLink("Home", "Index", "Home"))

                     .AppendHtml("</li>");



    if(SomeCondition())

    {

        content.AppendHtml(@"<div>

            Note `HtmlContentBuilder.AppendHtml()` is Mutable

            as well as Fluent/Chainable.

        </div>");

    }



    return content;

}

Finally in the razor view, we don't even need @Html.Raw(Html.GetContent()) anymore (which used to be required in ASP.NET MVC 5), just calling @Html.GetContent() is sufficient and Razor will take care of all the escaping business.