System.Net.Http.Headers

HttpClient.Headers

Provides access to the collection of HTTP headers associated with an HttpClient instance.

Summary

Used to add, remove, or get specific HTTP headers.
Typically accessed via the DefaultRequestHeaders property of a HttpClient object.
Supports standard headers like User-Agent, Accept, Content-Type, etc.

Properties

`DefaultRequestHeaders`

Gets the dictionary of HTTP headers that will be sent with every request made using this HttpClient instance.

public HttpRequestHeaders DefaultRequestHeaders { get; }

This property is the primary way to interact with the headers for outgoing requests.

Usage Examples

Adding a custom header:


using System.Net.Http;
using System.Net.Http.Headers;

var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-My-Custom-Header", "MyValue");
var response = await client.GetAsync("https://example.com");

Adding a standard header (e.g., User-Agent):


using System.Net.Http;
using System.Net.Http.Headers;

var client = new HttpClient();
client.DefaultRequestHeaders.UserAgent.ParseAdd("MyAwesomeApp/1.0");
var response = await client.GetAsync("https://example.com");

Removing a header:


using System.Net.Http;
using System.Net.Http.Headers;

var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-ToRemove", "SomeValue");
if (client.DefaultRequestHeaders.Contains("X-ToRemove"))
{
    client.DefaultRequestHeaders.Remove("X-ToRemove");
}
var response = await client.GetAsync("https://example.com");

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