This is my validation code:

public class XMLValidator
{
// Validation Error Count
static int ErrorsCount = 0;

// Construct a validation error message
static string ErrorMessage = "";

private static void ValidationHandler(object sender,
ValidationEventArgs e)
{
if (e.Severity == XmlSeverityType.Error || e.Severity ==
XmlSeverityType.Warning)
{
ErrorsCount++;
ErrorMessage += String.Format(ErrorsCount + ". Line {0},
Position {1} \"{2}\"",
e.Exception.LineNumber, e.Exception.LinePosition,
e.Exception.Message) + "\r\n";
}

}

public String Validate(string XMLDoc, string XSDSchema)
{
String ValidationMessage = null;

// Create the XmlSchemaSet class
XmlSchemaSet sc = new XmlSchemaSet();

// Add the schema to the collection
sc.Add(null, XSDSchema);

// Set the validation settings
XmlReaderSettings settings = new XmlReaderSettings();
settings.ValidationType = ValidationType.Schema;
settings.Schemas = sc;
settings.ValidationEventHandler += new ValidationEventHandler
(ValidationHandler);
settings.ValidationFlags =
XmlSchemaValidationFlags.ReportValidationWarnings |
XmlSchemaValidationFlags.ProcessIdentityConstraints |
XmlSchemaValidationFlags.ProcessInlineSchema |
XmlSchemaValidationFlags.ProcessSchemaLocation;
settings.CloseInput = true;

// Create the XmlReader object
XmlReader reader = XmlReader.Create(XMLDoc, settings);

// Parse the file
while (reader.Read()) ;

if (ErrorsCount > 0)
{
// XML validation failed
ValidationMessage = ErrorMessage;
}
return ValidationMessage;
}
}

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