HeaderDictionaryDecoratorExtensions Class

Definition

Namespace

Cuemon.AspNetCore.Http

Assemblies

Cuemon.AspNetCore.dll

Source

src/Cuemon.AspNetCore/Extensions/Http/HeaderDictionaryDecoratorExtensions.cs

Extension methods for the IHeaderDictionary interface hidden behind the IDecorator<T> interface.

public static class HeaderDictionaryDecoratorExtensions

Inheritance

object

HeaderDictionaryDecoratorExtensions

Examples

HeaderDictionaryDecoratorExtensions provides extension methods on Decorator.Enclose for merging, sanitizing, and updating IHeaderDictionary instances. This example creates a target HeaderDictionary with "X-Existing" and a source with both "X-Existing" and "X-New", then calls AddRange to selectively add only non-existing headers. It also demonstrates AddOrUpdateHeader with control-character sanitization (removing \r\n from a value) and AddOrUpdateHeaders to copy HttpResponseMessage response headers into the target. Console output confirms "X-Existing" retains its original value, "X-New" is added, sanitized headers are cleaned to "helloworld", and response headers are merged as "alpha,beta".

using System;
using System.Net.Http;
using Cuemon;
using Cuemon.AspNetCore.Http;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Primitives;

namespace MyApp.AspNetCore.Http
{
    public class HeaderDictionaryDecoratorExtensionsExample
    {
        public void Demonstrate()
        {
            // Add non-existing headers from one dictionary into another
            var target = new HeaderDictionary
            {
                { "X-Existing", "value1" }
            };

            var source = new HeaderDictionary
            {
                { "X-Existing", "value1" },
                { "X-New", "value2" }
            };

            // Only adds headers that do not already exist in target
            Decorator.Enclose<IHeaderDictionary>(target).AddRange(source);

            Console.WriteLine(target["X-Existing"]); // "value1"
            Console.WriteLine(target["X-New"]);      // "value2"

            // Add or update a single header with control-character sanitization
            Decorator.Enclose<IHeaderDictionary>(target).AddOrUpdateHeader(
                "X-Sanitized", new StringValues("hello\r\nworld"), useAsciiEncodingConversion: false);

            Console.WriteLine(target["X-Sanitized"]); // "helloworld"

            // Copy response headers into an IHeaderDictionary
            using var response = new HttpResponseMessage();
            response.Headers.Add("X-Custom", new[] { "alpha", "beta" });

            Decorator.Enclose<IHeaderDictionary>(target).AddOrUpdateHeaders(response.Headers);

            Console.WriteLine(target["X-Custom"]); // "alpha,beta"

}}
}

Methods

Name	Description
AddOrUpdateHeader(IDecorator<IHeaderDictionary>, string, StringValues, bool)	Attempts to add or update an existing element with the provided key and value to the enclosed IHeaderDictionary of the decorator.
AddOrUpdateHeaders(IDecorator<IHeaderDictionary>, HttpResponseHeaders)	Attempts to add or update one or more elements from the provided collection of responseHeaders to the enclosed IHeaderDictionary of the decorator.
AddRange(IDecorator<IHeaderDictionary>, IHeaderDictionary, Func<KeyValuePair<string, StringValues>, IHeaderDictionary, bool>)	Adds a range of headers to the enclosed IHeaderDictionary.

See Also

IDecorator<T>

Decorator<T>