Getting the HTML for a ViewResult in ASP.NET Core
This is another post tagged “hack”: this time, how to get the HTML for a rendered view, in code. This is a standard solution that does not use any kind of reflection (or other) magic.
So, the idea is to pick up a ViewResult (it will also work for a PartialViewResult, but, alas, they do not share a common class – see #6984) and call some method, say, ToHtml, to get the rendered output. This method can look like this:
public static class ViewResultExtensions
{
public static string ToHtml(this ViewResult result, HttpContext httpContext)
{
var feature = httpContext.Features.Get<IRoutingFeature>();
var routeData = feature.RouteData;
var viewName = result.ViewName ?? routeData.Values["action"] as string;
var actionContext = new ActionContext(httpContext, routeData, new ControllerActionDescriptor());
var options = httpContext.RequestServices.GetRequiredService<IOptions<MvcViewOptions>>();
var htmlHelperOptions = options.Value.HtmlHelperOptions;
var viewEngineResult = result.ViewEngine?.FindView(actionContext, viewName, true) ?? options.Value.ViewEngines.Select(x => x.FindView(actionContext, viewName, true)).FirstOrDefault(x => x != null);
var view = viewEngineResult.View;
var builder = new StringBuilder();
using (var output = new StringWriter(builder))
{
var viewContext = new ViewContext(actionContext, view, result.ViewData, result.TempData, output, htmlHelperOptions);
view
.RenderAsync(viewContext)
.ConfigureAwait(false)
.GetAwaiter()
.GetResult();
}
return builder.ToString();
}
}
To use it, just do:
var view = this.View(“ViewName”);Have fun!
var html = view.ToHtml();
