/// <summary>
/// Asynchronously renders the specified <paramref name="view"/> to the response body.
/// </summary>
/// <param name="view">The <see cref="IView"/> to render.</param>
/// <param name="actionContext">The <see cref="ActionContext"/> for the current executing action.</param>
/// <param name="viewData">The <see cref="ViewDataDictionary"/> for the view being rendered.</param>
/// <param name="tempData">The <see cref="ITempDataDictionary"/> for the view being rendered.</param>
/// <returns>A <see cref="Task"/> that represents the asynchronous rendering.</returns>
public static async Task ExecuteAsync([NotNull] IView view,
[NotNull] ActionContext actionContext,
[NotNull] ViewDataDictionary viewData,
[NotNull] ITempDataDictionary tempData,
[NotNull] HtmlHelperOptions htmlHelperOptions,
MediaTypeHeaderValue contentType)
{
var response = actionContext.HttpContext.Response;
contentType = contentType ?? DefaultContentType;
if (contentType.Encoding == null)
{
// Do not modify the user supplied content type, so copy it instead
contentType = contentType.Copy();
contentType.Encoding = Encoding.UTF8;
}
response.ContentType = contentType.ToString();
using (var writer = new HttpResponseStreamWriter(response.Body, contentType.Encoding))
{
var viewContext = new ViewContext(
actionContext,
view,
viewData,
tempData,
writer,
htmlHelperOptions);
await view.RenderAsync(viewContext);
}
}
public void Copy_SimpleMediaType_Copied()
{
var mediaType0 = new MediaTypeHeaderValue("text/plain");
var mediaType1 = mediaType0.Copy();
Assert.NotSame(mediaType0, mediaType1);
Assert.Same(mediaType0.MediaType, mediaType1.MediaType);
Assert.NotSame(mediaType0.Parameters, mediaType1.Parameters);
Assert.Equal(mediaType0.Parameters.Count, mediaType1.Parameters.Count);
}
public void Copy_SimpleMediaType_Copied()
{
var mediaType0 = new MediaTypeHeaderValue("text/plain");
var mediaType1 = mediaType0.Copy();
Assert.NotSame(mediaType0, mediaType1);
Assert.Same(mediaType0.MediaType, mediaType1.MediaType);
Assert.NotSame(mediaType0.Parameters, mediaType1.Parameters);
Assert.Equal(mediaType0.Parameters.Count, mediaType1.Parameters.Count);
}
public void Copy_WithParameters_Copied()
{
var mediaType0 = new MediaTypeHeaderValue("text/plain");
mediaType0.Parameters.Add(new NameValueHeaderValue("name", "value"));
var mediaType1 = mediaType0.Copy();
Assert.NotSame(mediaType0, mediaType1);
Assert.Same(mediaType0.MediaType, mediaType1.MediaType);
Assert.NotSame(mediaType0.Parameters, mediaType1.Parameters);
Assert.Equal(mediaType0.Parameters.Count, mediaType1.Parameters.Count);
var pair0 = mediaType0.Parameters.First();
var pair1 = mediaType1.Parameters.First();
Assert.NotSame(pair0, pair1);
Assert.Same(pair0.Name, pair1.Name);
Assert.Same(pair0.Value, pair1.Value);
}
public void Copy_WithParameters_Copied()
{
var mediaType0 = new MediaTypeHeaderValue("text/plain");
mediaType0.Parameters.Add(new NameValueHeaderValue("name", "value"));
var mediaType1 = mediaType0.Copy();
Assert.NotSame(mediaType0, mediaType1);
Assert.Same(mediaType0.MediaType, mediaType1.MediaType);
Assert.NotSame(mediaType0.Parameters, mediaType1.Parameters);
Assert.Equal(mediaType0.Parameters.Count, mediaType1.Parameters.Count);
var pair0 = mediaType0.Parameters.First();
var pair1 = mediaType1.Parameters.First();
Assert.NotSame(pair0, pair1);
Assert.Same(pair0.Name, pair1.Name);
Assert.Same(pair0.Value, pair1.Value);
}
/// <summary>
/// Asynchronously renders the specified <paramref name="view"/> to the response body.
/// </summary>
/// <param name="view">The <see cref="IView"/> to render.</param>
/// <param name="actionContext">The <see cref="ActionContext"/> for the current executing action.</param>
/// <param name="viewData">The <see cref="ViewDataDictionary"/> for the view being rendered.</param>
/// <param name="tempData">The <see cref="ITempDataDictionary"/> for the view being rendered.</param>
/// <returns>A <see cref="Task"/> that represents the asynchronous rendering.</returns>
public static async Task ExecuteAsync(
IView view,
ActionContext actionContext,
ViewDataDictionary viewData,
ITempDataDictionary tempData,
HtmlHelperOptions htmlHelperOptions,
MediaTypeHeaderValue contentType)
{
if (view == null)
{
throw new ArgumentNullException(nameof(view));
}
if (actionContext == null)
{
throw new ArgumentNullException(nameof(actionContext));
}
if (viewData == null)
{
throw new ArgumentNullException(nameof(viewData));
}
if (tempData == null)
{
throw new ArgumentNullException(nameof(tempData));
}
if (htmlHelperOptions == null)
{
throw new ArgumentNullException(nameof(htmlHelperOptions));
}
var response = actionContext.HttpContext.Response;
if (contentType != null && contentType.Encoding == null)
{
// Do not modify the user supplied content type, so copy it instead
contentType = contentType.Copy();
contentType.Encoding = Encoding.UTF8;
}
// Priority list for setting content-type:
// 1. passed in contentType (likely set by the user on the result)
// 2. response.ContentType (likely set by the user in controller code)
// 3. ViewExecutor.DefaultContentType (sensible default)
response.ContentType = contentType?.ToString() ?? response.ContentType ?? DefaultContentType.ToString();
using (var writer = new HttpResponseStreamWriter(response.Body, contentType?.Encoding ?? DefaultContentType.Encoding))
{
var viewContext = new ViewContext(
actionContext,
view,
viewData,
tempData,
writer,
htmlHelperOptions);
await view.RenderAsync(viewContext);
// Invoke FlushAsync to ensure any buffered content is asynchronously written to the underlying
// response. In the absence of this line, the buffer gets synchronously written to the response
// as part of the Dispose which has a perf impact.
await writer.FlushAsync();
}
}
/// <summary>
/// Executes a view asynchronously.
/// </summary>
/// <param name="actionContext">The <see cref="ActionContext"/> associated with the current request.</param>
/// <param name="view">The <see cref="IView"/>.</param>
/// <param name="viewData">The <see cref="ViewDataDictionary"/>.</param>
/// <param name="tempData">The <see cref="ITempDataDictionary"/>.</param>
/// <param name="contentType">
/// The content-type header value to set in the response. If <c>null</c>, <see cref="DefaultContentType"/> will be used.
/// </param>
/// <param name="statusCode">
/// The HTTP status code to set in the response. May be <c>null</c>.
/// </param>
/// <returns>A <see cref="Task"/> which will complete when view execution is completed.</returns>
public virtual async Task ExecuteAsync(
ActionContext actionContext,
IView view,
ViewDataDictionary viewData,
ITempDataDictionary tempData,
MediaTypeHeaderValue contentType,
int? statusCode)
{
if (actionContext == null)
{
throw new ArgumentNullException(nameof(actionContext));
}
if (view == null)
{
throw new ArgumentNullException(nameof(view));
}
var services = actionContext.HttpContext.RequestServices;
if (viewData == null)
{
var metadataProvider = services.GetRequiredService<IModelMetadataProvider>();
viewData = new ViewDataDictionary(metadataProvider);
}
if (tempData == null)
{
tempData = services.GetRequiredService<ITempDataDictionary>();
}
var response = actionContext.HttpContext.Response;
if (contentType != null && contentType.Encoding == null)
{
// Do not modify the user supplied content type, so copy it instead
contentType = contentType.Copy();
contentType.Encoding = Encoding.UTF8;
}
// Priority list for setting content-type:
// 1. passed in contentType (likely set by the user on the result)
// 2. response.ContentType (likely set by the user in controller code)
// 3. ViewExecutor.DefaultContentType (sensible default)
response.ContentType = contentType?.ToString() ?? response.ContentType ?? DefaultContentType.ToString();
if (statusCode != null)
{
response.StatusCode = statusCode.Value;
}
var encoding = contentType?.Encoding ?? DefaultContentType.Encoding;
using (var writer = WriterFactory.CreateWriter(response.Body, encoding))
{
var viewContext = new ViewContext(
actionContext,
view,
viewData,
tempData,
writer,
ViewOptions.HtmlHelperOptions);
DiagnosticSource.BeforeView(view, viewContext);
await view.RenderAsync(viewContext);
DiagnosticSource.AfterView(view, viewContext);
// Perf: Invoke FlushAsync to ensure any buffered content is asynchronously written to the underlying
// response asynchronously. In the absence of this line, the buffer gets synchronously written to the
// response as part of the Dispose which has a perf impact.
await writer.FlushAsync();
}
}