Error validating Xml against Xsd Schema - validation

Question

I have the following Xml which I want to validate against Xsd Schema (below).
I am trying to validate the Xml against the given Xsd Schema using the C# function given below. I am getting this generic kind error message "Data at the root level is invalid. Line 1, position 1". This happens at "while(vr.Read())".
Can you please explain what is the cause and resolution to this problem or is there a way I can troubleshoot these type of generic errors.
As you can see from my Xsd schema that it has references to other child xsd files also. I am wondering if it has something to do with the error.
Warm Regards
XML File
<?xml version="1.0" encoding="utf-8"?>
<n1:Form109495CTransmittalUpstream xmlns="urn:us:gov:treasury:irs:ext:aca:air:6.2" xmlns:irs="urn:us:gov:treasury:irs:common" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:n1="urn:us:gov:treasury:irs:msg:form1094-1095Ctransmitterupstreammessage" xsi:schemaLocation="urn:us:gov:treasury:irs:msg:form1094-1095Ctransmitterupstreammessage IRS-Form1094-1095CTransmitterUpstreamMessage.xsd">
<Form1094CUpstreamDetail recordType="C" lineNum="0">
<--MORE XML TAGS HERE -->
</Form1094CUpstreamDetail>
</n1:Form109495CTransmittalUpstream>
XSD Schema
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns="urn:us:gov:treasury:irs:msg:form1094-1095Ctransmitterupstreammessage"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:irs="urn:us:gov:treasury:irs:common"
xmlns:air6.2="urn:us:gov:treasury:irs:ext:aca:air:6.2"
targetNamespace="urn:us:gov:treasury:irs:msg:form1094-1095Ctransmitterupstreammessage"
elementFormDefault="qualified" attributeFormDefault="unqualified" version="1.0">
<xsd:annotation>
<xsd:appinfo>
<release>ACA Release 6.2</release>
</xsd:appinfo>
<xsd:documentation>Form-1094C (Issuer) Transmittal and Form 1095C - Transmittal of Health Insurance Coverage Statements
<VersionNum>5.2</VersionNum>
<VersionEffectiveBeginDt>2015-01-06</VersionEffectiveBeginDt>
</xsd:documentation>
</xsd:annotation>
<!-- ===== Imports ===== -->
<xsd:import namespace="urn:us:gov:treasury:irs:common" schemaLocation="common-IRS-CAC.xsd"/>
<xsd:import namespace="urn:us:gov:treasury:irs:ext:aca:air:6.2"
schemaLocation="ext-IRS-EXT-ACA-AIR-6.2.xsd"/>
<xsd:element name="Form109495CTransmittalUpstream" type="Form109495CTransmittalUpstreamType">
<xsd:annotation>
<xsd:documentation>
<Component>
<DictionaryEntryNm>Form109495C Transmission Upstream</DictionaryEntryNm>
<MajorVersionNum>1</MajorVersionNum>
<MinorVersionNum>1</MinorVersionNum>
<VersionEffectiveBeginDt>2015-01-06</VersionEffectiveBeginDt>
<VersionDescriptionTxt>Initial Version</VersionDescriptionTxt>
<DescriptionTxt>The elements associated with 1094C data generated EOY report</DescriptionTxt>
</Component>
</xsd:documentation>
</xsd:annotation>
</xsd:element>
<xsd:complexType name="Form109495CTransmittalUpstreamType">
<xsd:annotation>
<xsd:documentation>
<Component>
<DictionaryEntryNm>Form109495C Transmission Upstream Type</DictionaryEntryNm>
<MajorVersionNum>1</MajorVersionNum>
<MinorVersionNum>1</MinorVersionNum>
<VersionEffectiveBeginDt>2014-11-05</VersionEffectiveBeginDt>
<VersionDescriptionTxt>Initial Version</VersionDescriptionTxt>
<DescriptionTxt>Transmission type for 1094C forms upstream data generated EOY report</DescriptionTxt>
</Component>
</xsd:documentation>
</xsd:annotation>
<xsd:sequence>
<xsd:element ref="air6.2:Form1094CUpstreamDetail" minOccurs="1" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
</xsd:schema>
Following is the C# Validation Function:
/// <SUMMARY>
/// This method validates an xml string against an xml schema.
/// </SUMMARY>
/// <PARAM name="xml">StringReader containing xml</PARAM>
/// <PARAM name="schemaNamespace">XML Schema Namespace</PARAM>
/// <PARAM name="schemaUri">XML Schema Uri</PARAM>
/// <RETURNS>bool</RETURNS>
public bool ValidXmlDoc(StringReader xml,
string schemaNamespace, string schemaUri)
{
// Continue?
if(xml == null || schemaNamespace == null || schemaUri == null)
{
return false;
}
isValidXml = true;
XmlValidatingReader vr;
XmlTextReader tr;
XmlSchemaCollection schemaCol = new XmlSchemaCollection();
schemaCol.Add(schemaNamespace, schemaUri);
try
{
// Read the xml.
tr = new XmlTextReader(xml);
// Create the validator.
vr = new XmlValidatingReader(tr);
// Set the validation tyep.
vr.ValidationType = ValidationType.Schema;
// Add the schema.
if(schemaCol != null)
{
vr.Schemas.Add(schemaCol);
}
// Set the validation event handler.
vr.ValidationEventHandler +=
new ValidationEventHandler(ValidationCallBack);
// Read the xml schema.
while(vr.Read())
{
}
vr.Close();
return isValidXml;
}
catch(Exception ex)
{
this.ValidationError = ex.Message;
return false;
}
finally
{
// Clean up...
vr = null;
tr = null;
}
}

Answer 1

AFAIK XmlValidatingReader is obsolete. I think you would be much better of using XmlReader. In order to control URI resolutions(should schema has references to other schemes as relative paths) you could create your own XML URL resolver class by inheriting from XmlUrlResolver and overriding ResolveUri method. Then assign it to the XmlResolver member of XmlReaderSettings class. But I hope things would not deteriorate to that, though.:) Hopefully.:) Here is schematic code I could suggest:
XmlTextReader reader = new XmlTextReader(pathToXSD);
XmlSchema schema = XmlSchema.Read(reader, ValidationEventHandler);
XmlReaderSettings settings = new XmlReaderSettings();
settings.ValidationType = ValidationType.Schema;
settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessInlineSchema;
settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessSchemaLocation;
settings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
settings.ValidationEventHandler += new ValidationEventHandler(ValidationEventHandler);
settings.Schemas.Add(schema);
using (StringReader xmlStream = new StringReader(xml))
{
using (XmlReader xmlReader = XmlReader.Create(xmlStream, settings))
{
while (xmlReader.Read()) { }
}
}