IXMLDOMSchemaCollection/XMLSchemaCache

The following code shows how to create XMLSchemaCache objects in Microsoft® JScript®.

var cache = new ActiveXObject("Msxml2.XMLSchemaCache.5.0");

The following code shows how to create XMLSchemaCache objects in Microsoft® Visual Basic® Scripting Edition (VBScript).

Dim cache
Set cache = CreateObject("Msxml2.XMLSchemaCache.5.0");

Example

The following example shows how to build a reusable schema cache.

1. Load a document that references schemas through x-schema.

   var xmldoc = new ActiveXObject("Msxml2.DOMDocument.5.0");
   xmldoc.async = false;
   xmldoc.load("http://myserver/mydata.xml");
   if (xmlDoc.parseError.errorCode <> 0) {
      var myErr = xmlDoc.parseError;
      alert("You have error " + myErr.reason);
   }

2. Build a cache from the schemas loaded by your document.

   var cache = new ActiveXObject("Msxml2.XMLSchemaCache.5.0");
   cache.addCollection(xmldoc.namespaces);

3. Now you can use this cache in the load method of another document.

   var xmldoc2 = new ActiveXObject("Msxml2.DOMDocument.5.0");
   xmldoc2.async = false;
   xmldoc2.schemas = cache;
   xmldoc2.load("http://myserver/newdata.xml");
   if (xmlDoc.parseError.errorCode <> 0) {
      var myErr = xmlDoc.parseError;
      alert("You have error " + myErr.reason);
   }

   The Xmldoc2 object will load much faster because the schemas are cached.

The IXMLDOMSchemaCollection implementation in MSXML 2.6 and 3.0 also supports the following interface through QueryInterface.

Return Values

E_FAIL

The attempt to modify a read-only object failed for one of the following reasons: argument is not a valid schema; invalid namespace URI; or document is not ready.

E_INVALIDARG

The parameter is incorrect.

E_OUTOFMEMORY

Out of memory.

E_POINTER

Invalid pointer.

Example

import "msxml5.dll"
using namespace MSXML2;

#define CHECK_AND_RELEASE(pInterface)  \
if(pInterface) \
   {\
pInterface->Release();\
pInterface = NULL;\
   }\

#define RELEASE(pInterface)  \
   {\
pInterface->Release();\
pInterface = NULL;\
   }\

BOOL DOMDocument2nameSpaces()
{
   BOOL bResult = FALSE;
   short sResult = FALSE;
   IXMLDOMElement *pIXMLDOMElement=NULL;
   IXMLDOMSchemaCollection *pIXMLDOMSchemaCollection=NULL;
   IXMLDOMDocument2 *pIXMLDOMDocument2=NULL;
   HRESULT hr;
   BSTR bstrValue;

   try
   {
      hr=CoCreateInstance(CLSID_DOMDocument, NULL, CLSCTX_SERVER, 
         IID_IXMLDOMDocument2, (LPVOID*)(&pIXMLDOMDocument2));
      SUCCEEDED(hr) ? 0 : throw hr;

      if(pIXMLDOMDocument2)
      {
         hr=pIXMLDOMDocument2->put_async(VARIANT_FALSE);
         if(SUCCEEDED(hr))
         {
            hr=pIXMLDOMDocument2->load(_variant_t( 
               _T("d:\\inetpub\\wwwroot\\samplexmldtd.xml")), &sResult);
            if(SUCCEEDED(hr) && (sResult==VARIANT_TRUE))
            {
               hr=pIXMLDOMDocument2->get_namespaces( 
                  &pIXMLDOMSchemaCollection);
               if(SUCCEEDED(hr))
               {
                  LONG uLength;

                  bResult=TRUE;
                  hr=pIXMLDOMSchemaCollection->get_length(&uLength);
                  if(SUCCEEDED(hr))
                  {
                     for(int iIndex=0; iIndex < uLength; iIndex++)
                     {
                        hr=pIXMLDOMSchemaCollection->get_namespaceURI( 
                           iIndex, &bstrValue);
                        if(SUCCEEDED(hr))
                           ::MessageBox(NULL, bstrValue, _T("Namespace"),
                           MB_OK);
                     }
                  }
               }
            }
         }
         RELEASE(pIXMLDOMDocument2);
      }
   }
   catch(...)
   {
      CHECK_AND_RELEASE(pIXMLDOMDocument2);
      DisplayErrorToUser();
   }
   return bResult;
}

d:\\inetpub\\wwwroot\\samplexmldtd.xml

<?xml version='1.0'?>
<COLLECTION xmlns:dt="urn:schemas-microsoft-com:datatypes">
  <DATE dt:dt="datetime">1998-10-13T15:56:00</DATE>
  <BOOK>
    <TITLE>Lover Birds</TITLE>
    <AUTHOR>Cynthia Randall</AUTHOR>
    <PUBLISHER>Lucerne Publishing</PUBLISHER>
  </BOOK>
</COLLECTION>

Output (in a message box)

urn:schemas-microsoft-com:datatypes

Header and IDL files: msxml2.h, msxml2.idl