validate Method1

Article
10/27/2016

Performs run-time validation on the currently loaded document using the currently loaded document type definition (DTD), schema, or schema collection.

MSXML 6.0 doesn't support XDR schemas; the validate method validates only against DTDs and XSD schemas.

JScript Syntax

objXMLDOMDocument2.validate();

Return Value

A ParseError object indicating exactly what error occurred, if any.

Example

The following Microsoft JScript example shows how to validate at runtime.

var xmldoc = new ActiveXObject("Msxml2.DOMDocument.3.0");  
xmldoc.async = false  
// This will validate on load because validateOnParse is set to true   
// by default.  
xmldoc.load("https://server/myData.xml");  
// You make a change to an attribute:  
xmldoc.documentElement.setAttribute("a", "123");  
// Now you want to verify your document is still valid:  
var err = xmldoc.validate();  
if (err.errorCode == 0)  
{  
   WScript.Echo("Document is valid");  
}  
else  
{  
   WScript.Echo("Validation error:" + err.reason);  
}

C/C++ Syntax

HRESULT validate(IXMLDOMParseError ** errorObj);

Return Values

An IErrorInfo containing a formatted error message indicating what went wrong, and one of the following HRESULTs (also returned in the ErrorInfo.Number property).

Return value	Hexadecimal value	Description
E_PENDING	0x8000000A	Document `readyState` is not 4, indicating the document is not completely loaded.
S_OK	0	The document is valid according to DTD or schemas.
S_FALSE	1	The document is invalid according to DTD or schemas. For error information, see the returned `IXMLDOMParseError` object.

The following possible validation errors returned with S_FALSE are listed, together with the errorCode value.

Message ID	Error Code (Hex Value)	Message
XML_E_NODTD	0xC00CE224	The `validate` method failed because a DTD or schema was not specified in the document.
XML_E_NOTWF	0xC00CE223	The `validate` method failed because the document does not contain exactly one root node.
XML_ENTITY_UNDEFINED	0xC00CE002	Reference to undefined entity '%1'.
XML_INFINITE_ENTITY_LOOP	0xC00CE003	Entity '%1' contains an infinite entity reference loop.
XML_NDATA_INVALID_PE	0xC00CE004	Cannot use the NDATA keyword in a parameter entity declaration.
XML_REQUIRED_NDATA	0xC00CE005	Cannot use a general parsed entity '%1' as the value for attribute '%2'.
XML_NDATA_INVALID_REF	0xC00CE006	Cannot use unparsed entity '%1' in an entity reference.
XML_EXTENT_IN_ATTR	0xC00CE007	Cannot reference an external general parsed entity '%1' in an attribute value.
XML_ELEMENT_UNDECLARED	0xC00CE00D	The element '%1' is used but not declared in the DTD or schema.
XML_ELEMENT_ID_NOT_FOUND	0xC00CE00E	The attribute '%1' references the ID '%2', which is not defined in the document.
XML_EMPTY_NOT_ALLOWED	0xC00CE011	Element cannot be empty according to the DTD or schema.
XML_ELEMENT_NOT_COMPLETE	0xC00CE012	Element content is incomplete according to the DTD or schema.
XML_ROOT_NAME_MISMATCH	0xC00CE013	The name of the top-most element must match the name of the DOCTYPE declaration.
XML_INVALID_CONTENT	0xC00CE014	Element content is invalid according to the DTD or schema.
XML_ATTRIBUTE_NOT_DEFINED	0xC00CE015	The attribute '%1' on this element is not defined in the DTD or schema.
XML_ATTRIBUTE_FIXED	0xC00CE016	Attribute '%1' has a value that does not match the fixed value defined in the DTD or schema.
XML_ATTRIBUTE_VALUE	0xC00CE017	Attribute '%1' has an invalid value according to the DTD or schema.
XML_ILLEGAL_TEXT	0xC00CE018	Text is not allowed in this element according to the DTD or schema.
XML_MULTI_FIXED_VALUES	0xC00CE019	An attribute declaration cannot contain multiple fixed values: '%1'.
XML_ELEMENT_UNDEFINED	0xC00CE01C	Reference to undeclared element: '%1'.
ML_XMLNS_FIXED	0xC00CE01E	Attribute '%1' must be a #FIXED attribute.
XML_REQUIRED_ATTRIBUTE_MISSING	0xC00CE020	Required attribute '%1' is missing.
XML_DTD_EXPECTING	0xC00CE026	Expecting: %1.

Remarks

This method only validates fully loaded documents (readyState == 4).

The validate method returns an IXMLDOMParseError that is independent of the value returned by the parseError property on a document. Only the errorCode and reason properties of the returned value are set.

Unlike the load method, validate will fail if there is no DTD or schema applied to the document element. Therefore, validate will not be able tell you whether the document is just well-formed.

The validate method does not parse new schemas, but can import a schema from a SchemaCache associated with the document through the schemas property. If there is no schema for a given namespace, the elements in that namespace will not be validated.

Versioning

Implemented in: MSXML 3.0 and MSXML 6.0

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