HttpResponseHeaderCollection Class

Definition

Namespace:

Windows.Web.Http.Headers

Provides a collection of the HTTP headers associated with an HTTP response.

public ref class HttpResponseHeaderCollection sealed : IIterable<IKeyValuePair<Platform::String ^, Platform::String ^> ^>, IMap<Platform::String ^, Platform::String ^>, IStringable

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
class HttpResponseHeaderCollection final : IIterable<IKeyValuePair<winrt::hstring, winrt::hstring const&>>, IMap<winrt::hstring, winrt::hstring const&>, IStringable

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
public sealed class HttpResponseHeaderCollection : IDictionary<string,string>, IEnumerable<KeyValuePair<string,string>>, IStringable

Public NotInheritable Class HttpResponseHeaderCollection
Implements IDictionary(Of String, String), IEnumerable(Of KeyValuePair(Of String, String)), IStringable

Inheritance

Object Platform::Object IInspectable HttpResponseHeaderCollection

Attributes

ContractVersionAttribute MarshalingBehaviorAttribute

Implements

IDictionary<String,String> IMap<Platform::String,Platform::String> IMap<winrt::hstring,winrt::hstring> IIterable<IKeyValuePair<K,V>> IEnumerable<KeyValuePair<K,V>> IEnumerable<KeyValuePair<String,String>> IIterable<IKeyValuePair<Platform::String,Platform::String>> IIterable<IKeyValuePair<winrt::hstring,winrt::hstring>> IStringable

Windows requirements

Device family	Windows 10 (introduced in 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (introduced in v1.0)

Examples

The following sample code shows a method to get and set response headers on an HttpResponseMessage object using the properties on the HttpResponseHeaderCollection object. The Windows.Web.Http.Headers namespace has a number of strongly-typed header collection and value classes for specific HTTP headers that can be used to get and set headers with validation.

using System;
using System.Collections.Generic;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Web.Http;
using Windows.Web.Http.Headers;

        void DemonstrateResponseHeaders() {

            DemonstrateHeaderResponseAge();
            DemonstrateHeaderResponseAllow();
            DemonstrateHeaderResponseCacheControl();
            DemonstrateHeaderResponseDate();
            DemonstrateHeaderResponseLocation();
            DemonstrateHeaderResponseProxyAuthenticate();

        }


        public void DemonstrateHeaderResponseAge()
        {
            var response = new HttpResponseMessage();

            // Set the header with a strong type.
            DateTimeOffset value = DateTimeOffset.UtcNow;
            response.Headers.Age = new TimeSpan(1, 35, 55); // 1 hour, 35 minutes, 55 seconds.

            // Get the strong type out
            System.Diagnostics.Debug.WriteLine("Age value in minutes: {0}", response.Headers.Age.Value.TotalMinutes);

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The Age ToString() results: {0}", response.Headers.Age.ToString());
        }


        public void DemonstrateHeaderResponseAllow()
        {
            var response = new HttpResponseMessage();

            // Set the header with a string
            response.Headers.Allow.TryParseAdd ("GET");

            // Set the header with a strong type
            response.Headers.Allow.Add(HttpMethod.Patch);

            // Get the strong type out
            foreach (var value in response.Headers.Allow)
            {
                System.Diagnostics.Debug.WriteLine("Allow value: {0}", value.Method);
            }

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The Allow ToString() results: {0}", response.Headers.Allow.ToString());
        }

        public void DemonstrateHeaderResponseCacheControl()
        {
            var response = new HttpResponseMessage();

            // Set the header with a string
            response.Headers.CacheControl.TryParseAdd("public");

            // Set the header with a strong type
            response.Headers.CacheControl.Add(new HttpNameValueHeaderValue("max-age", "30"));

            // Get the strong type out
            foreach (var value in response.Headers.CacheControl)
            {
                System.Diagnostics.Debug.WriteLine("CacheControl {0}={1}", value.Name, value.Value);
            }

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The CacheControl ToString() results: {0}", response.Headers.CacheControl.ToString());
        }

        public void DemonstrateHeaderResponseDate()
        {
            var response = new HttpResponseMessage();

            // Set the header with a strong type.
            response.Headers.Date = DateTimeOffset.UtcNow;

            // Get the strong type out
            System.Diagnostics.Debug.WriteLine("Date value in ticks: {0}", response.Headers.Date.Value.Ticks);

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The Date ToString() results: {0}", response.Headers.Date.ToString());
        }

        public void DemonstrateHeaderResponseLocation()
        {
            var response = new HttpResponseMessage();

            // Set the header with a strong type.
            response.Headers.Location = new Uri("http://example.com/");

            // Get the strong type out
            System.Diagnostics.Debug.WriteLine("Location absolute uri: {0}", response.Headers.Location.AbsoluteUri);

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The Location ToString() results: {0}", response.Headers.Location.ToString());
        }

        public void DemonstrateHeaderResponseProxyAuthenticate()
        {
            var response = new HttpResponseMessage();

            // Set the header with a strong type.
            response.Headers.ProxyAuthenticate.TryParseAdd("Basic");
            response.Headers.ProxyAuthenticate.Add(new HttpChallengeHeaderValue("authScheme", "authToken"));

            // Get the strong type out
            foreach (var value in response.Headers.ProxyAuthenticate)
            {
                System.Diagnostics.Debug.WriteLine("Proxy authenticate scheme and token: {0} {1}", value.Scheme, value.Token);
            }

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The ProxyAuthenticate ToString() results: {0}", response.Headers.ProxyAuthenticate.ToString());
        }

        public void DemonstrateHeaderResponseRetryAfter()
        {
            var response = new HttpResponseMessage();

            // Set the header with a strong type.
            HttpDateOrDeltaHeaderValue newvalue;
            bool parseOk = HttpDateOrDeltaHeaderValue.TryParse("", out newvalue);
            if (parseOk)
            {
                response.Headers.RetryAfter = newvalue;
            }

            // Get the strong type out
            System.Diagnostics.Debug.WriteLine("Date value in ticks: {0}", response.Headers.Date.Value.Ticks);

            // The ToString() is useful for diagnostics, too.
            System.Diagnostics.Debug.WriteLine("The Date ToString() results: {0}", response.Headers.Date.ToString());
        }

Remarks

The HttpResponseHeaderCollection is a collection of the HTTP headers associated with an HTTP response to an HTTP request message. The HttpResponseHeaderCollection object can be used to get or set the specific headers on the HTTP response. Most of the properties on the HttpResponseHeaderCollection object provide access for the value of a specific HTTP header.

The Headers property on HttpResponseMessage returns an HttpResponseHeaderCollection object. This is how an HttpResponseHeaderCollection is constructed.

Enumerating the collection in C# or Microsoft Visual Basic

You can iterate through an HttpResponseHeaderCollection object in C# or Microsoft Visual Basic. In many cases, such as using foreach syntax, the compiler does this casting for you and you won't need to cast to IEnumerable explicitly. If you do need to cast explicitly, for example if you want to call GetEnumerator, cast the collection object to IEnumerable<T> with a KeyValuePair of String and String as the constraint.

Properties

Age	Gets or sets the TimeSpan object that represents the value of an Age HTTP header on an HTTP response.
Allow	Gets the HttpMethodHeaderValueCollection of HttpMethod objects that represent the value of an Allow HTTP header on an HTTP response.
CacheControl	Gets the HttpCacheDirectiveHeaderValueCollection of objects that represent the value of a Cache-Control HTTP header on an HTTP response.
Connection	Gets the HttpConnectionOptionHeaderValueCollection of HttpConnectionOptionHeaderValue objects that represent the value of a Connection HTTP header on an HTTP response.
Date	Gets or sets the DateTime object that represents the value of a Date HTTP header on an HTTP response.
Location	Gets or sets the Uri that represents the value or a Location HTTP header on an HTTP response.
ProxyAuthenticate	Gets the HttpChallengeHeaderValueCollection of HttpChallengeHeaderValue objects that represent the value of a Proxy-Authenticate HTTP header on an HTTP response.
RetryAfter	Gets or sets the HttpDateOrDeltaHeaderValue object that represent the value of a Retry-After HTTP header on an HTTP response.
Size	Gets the number of objects in the HttpResponseHeaderCollection.
TransferEncoding	Gets the HttpTransferCodingHeaderValueCollection of HttpTransferCodingHeaderValue objects that represent the value of a Transfer-Encoding HTTP header on an HTTP response.
WwwAuthenticate	Gets the HttpChallengeHeaderValueCollection of HttpChallengeHeaderValue objects that represent the value of a WWW-Authenticate HTTP header on an HTTP response.

Methods

Append(String, String)	Adds a new item to the end of the HttpResponseHeaderCollection.
Clear()	Removes all objects from the collection.
First()	Retrieves an iterator to the first item in the HttpResponseHeaderCollection.
GetView()	Returns an immutable view of the HttpResponseHeaderCollection.
HasKey(String)	Determines whether the HttpResponseHeaderCollection contains the specified key.
Insert(String, String)	Inserts or replaces an item in the HttpResponseHeaderCollection with the specified key and value.
Lookup(String)	Lookup an item in the HttpResponseHeaderCollection.
Remove(String)	Removes an item with a given key from the HttpResponseHeaderCollection.
ToString()	Returns a string that represents the current HttpResponseHeaderCollection object.
TryAppendWithoutValidation(String, String)	Try to append the specified item to the HttpResponseHeaderCollection without validation.

See also

• HttpResponseMessage
• Headers
• IMap<K,V>
• IIterable<T>
• IStringable