This class contains the headers that are part of a WebRequest or WebResponse . Some headers should not be accessed through this collection. Instead, use the corresponding properties of the WebRequest or WebResponse (or the HTTP-specific subclasses). These headers are Accept, Connection, Content-Length, Content-Type, Date, Expect, Host, Range, Referer, Transfer-Encoding, and User-Agent. public class WebHeaderCollection : System.Collections.Specialized.NameValueCollection { // Public Constructors public WebHeaderCollection ( ); // Protected Constructors protected WebHeaderCollection (System.Runtime.Serialization.SerializationInfo serializationInfo , System.Runtime.Serialization.StreamingContext streamingContext ); // Public Static Methods public static bool IsRestricted (string headerName ); // Public Instance Methods public void Add (string header ); public override void Add (string name , string value ); // overrides NameValueCollection public override string[ ] GetValues (string header ); // overrides NameValueCollection public override void OnDeserialization (object sender ); // overrides System.Collections.Specialized.NameObjectCollectionBase public override void Remove (string name ); // overrides NameValueCollection public override void Set (string name , string value ); // overrides NameValueCollection public byte[ ] ToByteArray ( ); public override string ToString ( ); // overrides object // Protected Instance Methods protected void AddWithoutValidate (string headerName , string headerValue ); } HierarchySystem.Object System.Collections.Specialized.NameObjectCollectionBase(System.Collections.ICollection , System.Collections.IEnumerable , System.Runtime.Serialization.ISerializable , System.Runtime.Serialization.IDeserializationCallback) System.Collections.Specialized.NameValueCollection WebHeaderCollection Returned ByWebClient.{Headers , ResponseHeaders} , WebRequest.Headers , WebResponse.Headers Passed ToHttpContinueDelegate.{BeginInvoke( ) , Invoke( )} , WebClient.Headers , WebRequest.Headers |