How to programmatically add or remove an ISAPI filter in IIS by using ADSI (302988)

SUMMARY

Global and site-level Internet Server Application Programming Interface (ISAPI) filter information is stored in the Internet Information Server (IIS) metabase or the Internet Information Services (IIS) metabase. You can access the metabase programmatically through the IIS Admin Objects (IISAO), which uses Active Directory Service Interfaces (ADSI), or through the IIS Admin Base Object (IISABO), which uses Microsoft Visual C++ interfaces. This article describes how to add and remove ISAPI filters in IIS by using ADSI.

Note The sample code in this article must be run with the security context of a member of the local Administrators group on the IIS server.

Remove an ISAPI filter by using ADSI

The following sample code removes a global filter named "myFilter" from the ISAPI filters list on the master properties of the WWW Publishing service.

    Dim objFilterProps, objFilters
    Dim strLoadOrder
    Dim strFilterName
    Dim intStartFilt

    strFilterName = "myFilter"

    Set objFilters = GetObject("IIS://LocalHost/W3SVC/Filters")
    strLoadOrder = objFilters.FilterLoadOrder
    If strLoadOrder <> "" Then
       If Right(strLoadOrder, 1) <> "," Then
          strLoadOrder = strLoadOrder & ","
       End If
       intStartFilt = InStr(strLoadOrder, strFilterName)
       strLoadOrder = Mid(strLoadOrder, 1, intStartFilt - 1) & _
          Mid(strLoadOrder, intStartFilt + Len(strFilterName) + 1, _
             Len(strLoadOrder))
       objFilters.FilterLoadOrder= strLoadOrder
       objFilters.SetInfo
       objFilters.Delete "IIsFilter", strFilterName
    End If
    Set objFilters = Nothing
				

Note that to remove the ISAPI filter from memory, you must restart IISADMIN service.

Troubleshooting

The example that is provided in this article demonstrates how to add and remove global ISAPI filters. To add or remove site-level ISAPI filters, use GetObject("IIS://LocalHost/W3SVC/1/Filters") to reference the correct metabase node, instead of the GetObject("IIS://LocalHost/W3SVC/Filters") example that is used in this article. The "1" in "/W3SVC/1/" refers to the metabase site instance ID of the particular Web site (in this case, the default Web site).