System.Xml.Schema.XmlSchemaValidator.CheckXsiTypeAndNil C# (CSharp) Méthode

        private SchemaElementDecl CheckXsiTypeAndNil(SchemaElementDecl elementDecl, string xsiType, string xsiNil, ref bool declFound)
        {
            XmlQualifiedName xsiTypeName = XmlQualifiedName.Empty;
            if (xsiType != null)
            {
                object typedVal = null;
                Exception exception = s_dtQName.TryParseValue(xsiType, _nameTable, _nsResolver, out typedVal);
                if (exception != null)
                {
                    SendValidationEvent(SR.Sch_InvalidValueDetailedAttribute, new string[] { "type", xsiType, s_dtQName.TypeCodeString, exception.Message }, exception);
                }
                else
                {
                    xsiTypeName = typedVal as XmlQualifiedName;
                }
            }
            if (elementDecl != null)
            { //nillable is not dependent on xsi:type.
                if (elementDecl.IsNillable)
                {
                    if (xsiNil != null)
                    {
                        _context.IsNill = XmlConvert.ToBoolean(xsiNil);
                        if (_context.IsNill && elementDecl.Presence == SchemaDeclBase.Use.Fixed)
                        {
                            Debug.Assert(elementDecl.DefaultValueTyped != null);
                            SendValidationEvent(SR.Sch_XsiNilAndFixed);
                        }
                    }
                }
                else if (xsiNil != null)
                {
                    SendValidationEvent(SR.Sch_InvalidXsiNill);
                }
            }
            if (xsiTypeName.IsEmpty)
            {
                if (elementDecl != null && elementDecl.IsAbstract)
                {
                    SendValidationEvent(SR.Sch_AbstractElement, QNameString(_context.LocalName, _context.Namespace));
                    elementDecl = null;
                }
            }
            else
            {
                SchemaElementDecl elementDeclXsi = _compiledSchemaInfo.GetTypeDecl(xsiTypeName);
                XmlSeverityType severity = XmlSeverityType.Warning;
                if (HasSchema && _processContents == XmlSchemaContentProcessing.Strict)
                {
                    severity = XmlSeverityType.Error;
                }
                if (elementDeclXsi == null && xsiTypeName.Namespace == _nsXs)
                {
                    XmlSchemaType schemaType = DatatypeImplementation.GetSimpleTypeFromXsdType(xsiTypeName);
                    if (schemaType == null)
                    { //try getting complexType - xs:anyType
                        schemaType = XmlSchemaType.GetBuiltInComplexType(xsiTypeName);
                    }
                    if (schemaType != null)
                    {
                        elementDeclXsi = schemaType.ElementDecl;
                    }
                }
                if (elementDeclXsi == null)
                {
                    SendValidationEvent(SR.Sch_XsiTypeNotFound, xsiTypeName.ToString(), severity);
                    elementDecl = null;
                }
                else
                {
                    declFound = true;
                    if (elementDeclXsi.IsAbstract)
                    {
                        SendValidationEvent(SR.Sch_XsiTypeAbstract, xsiTypeName.ToString(), severity);
                        elementDecl = null;
                    }
                    else if (elementDecl != null && !XmlSchemaType.IsDerivedFrom(elementDeclXsi.SchemaType, elementDecl.SchemaType, elementDecl.Block))
                    {
                        SendValidationEvent(SR.Sch_XsiTypeBlockedEx, new string[] { xsiTypeName.ToString(), QNameString(_context.LocalName, _context.Namespace) });
                        elementDecl = null;
                    }
                    else
                    {
                        if (elementDecl != null)
                        { //Get all element decl properties before assigning xsi:type decl; nillable already checked
                            elementDeclXsi = elementDeclXsi.Clone(); //Before updating properties onto xsi:type decl, clone it
                            elementDeclXsi.Constraints = elementDecl.Constraints;
                            elementDeclXsi.DefaultValueRaw = elementDecl.DefaultValueRaw;
                            elementDeclXsi.DefaultValueTyped = elementDecl.DefaultValueTyped;
                            elementDeclXsi.Block = elementDecl.Block;
                        }
                        _context.ElementDeclBeforeXsi = elementDecl;
                        elementDecl = elementDeclXsi;
                    }
                }
            }
            return elementDecl;
        }