HttpWebRequest.Headers Property


Specifies a collection of the name/value pairs that make up the HTTP headers.

 virtual property System::Net::WebHeaderCollection ^ Headers { System::Net::WebHeaderCollection ^ get(); void set(System::Net::WebHeaderCollection ^ value); };
public override System.Net.WebHeaderCollection Headers { get; set; }
member this.Headers : System.Net.WebHeaderCollection with get, set
Public Overrides Property Headers As WebHeaderCollection

Property Value


A WebHeaderCollection that contains the name/value pairs that make up the headers for the HTTP request.



The following code example uses the Headers property to print the HTTP header name/value pairs to the console.

// Create a new 'HttpWebRequest' Object to the mentioned URL.
HttpWebRequest^ myHttpWebRequest = (HttpWebRequest^)( WebRequest::Create( "" ) );
// Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
HttpWebResponse^ myHttpWebResponse = (HttpWebResponse^)( myHttpWebRequest->GetResponse() );
Console::WriteLine( "\nThe HttpHeaders are \n\n\tName\t\tValue\n {0}", myHttpWebRequest->Headers );
// Print the HTML contents of the page to the console.
Stream^ streamResponse = myHttpWebResponse->GetResponseStream();
StreamReader^ streamRead = gcnew StreamReader( streamResponse );
array<Char>^ readBuff = gcnew array<Char>(256);
int count = streamRead->Read( readBuff, 0, 256 );
Console::WriteLine( "\nThe HTML contents of page the are  : \n\n " );
while ( count > 0 )
   String^ outputData = gcnew String( readBuff,0,count );
   Console::Write( outputData );
   count = streamRead->Read( readBuff, 0, 256 );
// Release the HttpWebResponse Resource.
// Create a new 'HttpWebRequest' Object to the mentioned URL.
HttpWebRequest myHttpWebRequest=(HttpWebRequest)WebRequest.Create("");
// Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
HttpWebResponse myHttpWebResponse=(HttpWebResponse)myHttpWebRequest.GetResponse();
Console.WriteLine("\nThe HttpHeaders are \n\n\tName\t\tValue\n{0}",myHttpWebRequest.Headers);
// Print the HTML contents of the page to the console.
Stream streamResponse=myHttpWebResponse.GetResponseStream();
StreamReader streamRead = new StreamReader( streamResponse );
Char[] readBuff = new Char[256];
int count = streamRead.Read( readBuff, 0, 256 );
Console.WriteLine("\nThe HTML contents of page the are  : \n\n ");	
while (count > 0)
    String outputData = new String(readBuff, 0, count);
    count = streamRead.Read(readBuff, 0, 256);
// Close the Stream object.
// Release the HttpWebResponse Resource.
     ' Create a new 'HttpWebRequest' Object to the mentioned URL.
     Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create(""), HttpWebRequest)
     ' Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
     Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
     Console.WriteLine(ControlChars.Cr + "The HttpHeaders are " + ControlChars.Cr + ControlChars.Cr + ControlChars.Tab + "Name" + ControlChars.Tab + ControlChars.Tab + "Value" + ControlChars.Cr + "{0}", myHttpWebRequest.Headers)

     ' Print the HTML contents of the page to the console. 
     Dim streamResponse As Stream = myHttpWebResponse.GetResponseStream()
     Dim streamRead As New StreamReader(streamResponse)
     Dim readBuff(256) As [Char]
     Dim count As Integer = streamRead.Read(readBuff, 0, 256)
     Console.WriteLine(ControlChars.Cr + "The HTML contents of page the are  : " + ControlChars.Cr + ControlChars.Cr + " ")
     While count > 0
         Dim outputData As New [String](readBuff, 0, count)
         count = streamRead.Read(readBuff, 0, 256)
     End While
' Close the Stream object.
' Release the HttpWebResponse Resource.


The Headers collection contains the protocol headers associated with the request. The following table lists the HTTP headers that are not stored in the Headers collection but are either set by the system or set by properties or methods.

Header Set by
Accept Set by the Accept property.
Connection Set by the Connection property and KeepAlive property.
Content-Length Set by the ContentLength property.
Content-Type Set by the ContentType property.
Expect Set by the Expect property.
Date Set by the Date property.
Host Set by the Host property.
If-Modified-Since Set by the IfModifiedSince property.
Range Set by the AddRange method.
Referer Set by the Referer property.
Transfer-Encoding Set by the TransferEncoding property (the SendChunked property must be true).
User-Agent Set by the UserAgent property.

The Add method throws an ArgumentException if you try to set one of these protected headers.

Changing the Headers property after the request has been started by calling GetRequestStream, BeginGetRequestStream, GetResponse, or BeginGetResponse method throws an InvalidOperationException.

You should not assume that the header values will remain unchanged, because Web servers and caches may change or add headers to a Web request.

Applies to