HttpResponse::AppendHeader Method (String^, String^)
Adds an HTTP header to the output stream.
Assembly: System.Web (in System.Web.dll)
Parameters
- name
-
Type:
System::String^
The name of the HTTP header to add to the output stream.
- value
-
Type:
System::String^
The string to append to the header.
| Exception | Condition |
|---|---|
| HttpException | The header is appended after the HTTP headers have been sent. |
If you use the AppendHeader method to send cache-specific headers and at the same time use the cache object model (Cache) to set cache policy, HTTP response headers that pertain to caching (Cache-Control, Expires, Last-Modified, Pragma, and Vary) might be deleted when the cache object model is used. This behavior enables ASP.NET to maintain the most restrictive settings. For example, consider a page that includes user controls. If those controls have conflicting cache policies, the most restrictive cache policy will be used. If one user control sets the header "Cache-Control: Public" and another user control sets the more restrictive header "Cache-Control: Private" via calls to SetCacheability, then the "Cache-Control: Private" header will be sent with the response.
For a list of standard HTTP/1.1 headers, see section 14, "Header Field Definitions," in the Hypertext Transfer Protocol -- HTTP/1.1 specification on the World Wide Web Consortium (W3C) Web site.
The following example calls the AppendHeader method to add a custom header to the HttpResponse object sent to the requesting client.
Available since 1.1