Thank you for answer but still I have problem.
Can i with this solution below, copy/append Item[2] in MainDataSource:
try
{
DataSource ds = DataSources["ReadFromDB"];
ds.QueryConnection.Execute();
string xpath = "/dfs:myFields/dfs:dataFields/tns:Response/tns:Result";
string value = ds.CreateNavigator().SelectSingleNode(xpath, NamespaceManager).InnerXml;
XPathNavigator nav = this.MainDataSource.CreateNavigator();
string sFromChoice = nav.SelectSingleNode("/dfs:myFields/my:myFields/my:Items", NamespaceManager).Value;
xpath = "dfs:myFields/dfs:dataFields/tns:ReadResponse/tns:ReadResult/tns:Item[2]";
XPathNavigator xn = ds.CreateNavigator().SelectSingleNode(xpath, NamespaceManager);
xpath = "/dfs:myFields/dfs:dataFields/tns:MainResponse/s1:MainResult/s1:List";
MainDataSource.CreateNavigator().SelectSingleNode(xpath, NamespaceManager).AppendChild(xn);
}
Now i have exception with : Schema validation found non-data type errors.
That's mean a have to search problem with shemas or that code is totaly wrong?