My objective is to validade a xml file against the xsd whitch is in a string variable. Ps.: I already wrote a question numbered 3072697 on Friday. But I couldn't add this code today.
book.xml:
<?xml version="1.0" encoding="utf-8"?>
<author  xmlns='urn:bookstore-schema' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'>
  <first-name>Herman</first-name>
  <last-name>Melville</last-name>
</author>
book.xsd:
<?xml version="1.0" encoding="utf-8"?>
<xs:schema id="NewDataSet" targetNamespace="urn:bookstore-schema" xmlns:mstns="urn:bookstore-schema" xmlns="urn:bookstore-schema" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" attributeFormDefault="qualified" elementFormDefault="qualified">
  <xs:element name="author">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="first-name" type="xs:string" minOccurs="0" />
        <xs:element name="last-name" type="xs:string" minOccurs="0" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="NewDataSet" msdata:IsDataSet="true" msdata:UseCurrentLocale="true">
    <xs:complexType>
      <xs:choice minOccurs="0" maxOccurs="unbounded">
        <xs:element ref="author" />
      </xs:choice>
    </xs:complexType>
  </xs:element>
</xs:schema>
The Xsd_after_saved() is woorking perfectlly In Xsd_after_saved(), every place I need to use the XSD, I got from file locally
public void Xsd_after_saved()
{
    XmlReaderSettings settings = new XmlReaderSettings();
    settings.ValidationEventHandler += this.ValidationEventHandler;
    settings.ValidationType = ValidationType.Schema;
    settings.Schemas.Add(null, XmlReader.Create(@"C:\book.xsd"));
    settings.CheckCharacters = true;
    XmlReader XmlValidatingReader = XmlReader.Create(@"C:\book.xml", settings);
    XmlTextReader Reader = new XmlTextReader(@"C:\book.xml");
    StreamReader SR = new StreamReader(@"C:\book.xsd");
    XmlSchema Schema = new XmlSchema();
    Schema = XmlSchema.Read(SR, ValidationEventHandler);
    XmlValidatingReader ValidatingReader = new XmlValidatingReader(Reader);
    ValidatingReader.ValidationType = ValidationType.Schema;
    ValidatingReader.Schemas.Add(Schema);
    try
    {
        XmlValidatingReader.Read();
        XmlValidatingReader.Close();
        ValidatingReader.ValidationEventHandler += ValidationEventHandler;
        while ((ValidatingReader.Read()))
        {
        }
        ValidatingReader.Close();
    }
    catch (Exception ex)
    {
        ValidatingReader.Close();
        XmlValidatingReader.Close();
    }
}
The Xsd_whithout_saved() is not working In Xsd_whithout_saved(), every place I need the XSD, I got from variable StreamReader named readerXsd whitch come from a string
public void  Xsd_whithout_saved()
{
    //>>>Here is the biggest diference from the method Xsd_after_saved: I manipulate the XSD as string because it will come from database and 
    //it will not allowed to be saved locally
    XmlDocument xmlDoc = new XmlDocument();
    xmlDoc.Load(@"C:\book.xsd");
    //In the futute, strArquivoInteiro will be fullfill by xsd comming from database as nvarchar(max) and I will not be allowed to save as a file locally
    string strArquivoInteiro = xmlDoc.OuterXml;
    byte[] byteArray = Encoding.ASCII.GetBytes(strArquivoInteiro);
    MemoryStream streamXSD = new MemoryStream(byteArray);
    //<<<
    StreamReader readerXsd = new StreamReader(streamXSD);
    XmlReaderSettings settings = new XmlReaderSettings();
    settings.ValidationEventHandler += this.ValidationEventHandler;
    settings.ValidationType = ValidationType.Schema;
    settings.Schemas.Add(null, XmlReader.Create(readerXsd));
    settings.CheckCharacters = true;
    XmlReader XmlValidatingReader = XmlReader.Create(@"C:\book.xml", settings);
    XmlTextReader Reader = new XmlTextReader(@"C:\book.xml");
    XmlSchema Schema = new XmlSchema();
    //IN THIS LINE I RECEIVED THE XmlException "Root Element is Missing" and I can't understand the reason
    Schema = XmlSchema.Read(readerXsd, ValidationEventHandler);
    XmlValidatingReader ValidatingReader = new XmlValidatingReader(Reader);
    ValidatingReader.ValidationType = ValidationType.Schema;
    ValidatingReader.Schemas.Add(Schema);
    try
    {
        XmlValidatingReader.Read();
        XmlValidatingReader.Close();
        ValidatingReader.ValidationEventHandler += ValidationEventHandler;
        while ((ValidatingReader.Read()))
        {
        }
        ValidatingReader.Close();
    }
    catch (Exception ex)
    {
        ValidatingReader.Close();
        XmlValidatingReader.Close();
    }
}
private void ValidationEventHandler(object sender, ValidationEventArgs args)
{
    //place to deal with xml file no valided
}
 
     
     
     
    