namespace OAuthClient; public class OriginHandler : DelegatingHandler { private readonly string _origin; public OriginHandler(string origin) { _origin = origin; InnerHandler = new HttpClientHandler(); } protected override Task SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { // Add the Origin header to the request if (!request.Headers.Contains("Origin")) { request.Headers.Add("Origin", _origin); } return base.SendAsync(request, cancellationToken); } }