What is httpContext.Response.SubStatusCode for?

What is httpContext.Response.SubStatusCode for? this 开发者_JAVA百科value is part of the IIS integration mode pipeline.

Substatus is a category within the main status code which provides a little more information about the nature of the condition raising the main status code.

For example, error 401 (unauthorised) has several substatus codes:

401.1 - Logon failed.
401.2 - Logon failed due to server configuration.
401.3 - Unauthorized due to ACL on resource.
401.4 - Authorization failed by filter.
401.5 - Authorization failed by ISAPI/CGI application.

The full reference for HTTP status and substatus codes in IIS 7 is here

It gives you status code of the http response. For more details check HttpResponse.SubStatusCode and Troubleshooting Failed Requests Using Tracing in IIS 7