Windows Dev Center

WebHeaderCollection.Item Property (HttpRequestHeader)

Gets or sets the specified request header.

Namespace:  System.Net
Assembly:  System.Net (in System.Net.dll)

Public Property Item ( _
	header As HttpRequestHeader _
) As String


Type: System.Net.HttpRequestHeader
The request header value.

Property Value

Type: System.String
A String instance containing the specified header value.


On a get or set operation, the request header specified in the header parameter is a restricted header. The WebHeaderCollection class does not allow a user to get or set instances of this restricted header in this WebHeaderCollection instance.

The Item(HttpRequestHeader) property can be used to get the value of a common header defined in the HttpRequestHeader enumeration for use by WebClient or HttpWebRequest classes.

The Item(String) property can also be used to set the name and value for a header in a WebHeaderCollection. When setting a header, both a header and value parameter must be passed. The value parameter must be specified as a string.

Some common headers defined in the HttpRequestHeader enumeration are considered restricted and are either exposed directly (such as Content-Type) or protected by the system and cannot be set in a WebHeaderCollection object. Any attempt to set one of these restricted headers in the WebHeaderCollection object throws an exception. If the WebHeaderCollection object is associated with a HttpWebRequest object, the exception is thrown by the Item(HttpRequestHeader) property. If the WebHeaderCollection object is associated with a WebClient object, the exception is thrown later when an attempt to send the WebClient request occurs.

For a list of restricted headers, see the Remarks in the WebHeaderCollection class.

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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