//<------------performs delete operation on DB and generates response msg accordingly.
XElement delete_elem <Key, Data>(XElement request_msg, DBEngine <Key, DBElement <Key, Data> > db)
{
Console.Write("\n Request to Delete DB Element");
XElement response_msg = new XElement("Query_Response");
XElement type = new XElement("Query_Type", "Delete");
XElement result = new XElement("Result", "Could not delete element");
try
{
Key k = (Key)Convert.ChangeType(request_msg.Element("Key").Value, typeof(Key));
Console.WriteLine(" with key - {0}", k);
if (db.remove(k))
{
result = new XElement("Result", "DB Element deleted successfully from database.");
}
else
{
result = new XElement("Result", "Could not delete element from database");
}
response_msg.Add(type);
response_msg.Add(result);
return(response_msg);
}
catch (NullReferenceException ex)
{
Console.WriteLine("\n XML file for request message is not in the expected format. A particular tag could not be found.\n Exception = {0}", ex);
response_msg.Add(type);
response_msg.Add(result);
return(response_msg);
}
}
static void Main(string[] args)
{
"Testing DBExtensions Package".title('=');
WriteLine();
DBElement <int, string> elem1 = new DBElement <int, string>("Element-7", "Description of Element-7");
elem1.payload = "Payload of element-7.";
elem1.children.AddRange(new List <int> {
8, 9
});
DBElement <int, string> elem2 = new DBElement <int, string>("Element-8", "Description of Element-8");
//elem2.payload = "Payload of element-8.";
DBElement <int, string> elem3 = new DBElement <int, string>("Element-9", "Description of Element-9");
elem3.payload = "Payload of element-3.";
DBEngine <int, DBElement <int, string> > db = new DBEngine <int, DBElement <int, string> >();
db.insert(7, elem1);
db.insert(8, elem2);
db.insert(9, elem3);
Write(" Created a new dataBase with following contents:");
db.showDB();
WriteLine("\n\n Now going to persist the database contents to an XML file.");
PersistEngine pe = new PersistEngine();
string file_name = pe.persistDB <int, DBElement <int, string>, string>(db);
WriteLine(" Database contents are saved as - {0}", file_name);
WriteLine("\n Going to remove all DB elements and load the xml file saved above.");
db.remove(7);
db.remove(8);
db.remove(9);
WriteLine(" DB contents before calling load-DB");
db.showDB();
WriteLine(" Now send command to load database from the XML file.");
pe.loadDB <int, DBElement <int, string>, string>(db, file_name);
Write(" DB contents after calling load-DB ");
db.showDB();
DBEngine <string, DBElement <string, List <string> > > db2 = new DBEngine <string, DBElement <string, List <string> > >();
Write("\n\n --- DBElement<string,List<string>> ---");
DBElement <string, List <string> > elem_str = new DBElement <string, List <string> >();
elem_str.name = "Element-One";
elem_str.descr = "DB Element whose key type is string and payload type is List of strings.";
elem_str.timeStamp = DateTime.Now;
elem_str.children = new List <string> {
"Two", "Three", "Four"
};
elem_str.payload = new List <string> {
"Element payload is of type List of strings.", "This is string two.", "And third"
};
elem_str.showEnumerableElement();
db2.insert("One", elem_str);
Write("\n\n --- DBEngine<string,List<string>> ---");
db2.showEnumerableDB();
XElement noSqlDb = new XElement("NoSqlDb");
XElement keyType = new XElement("KeyType", typeof(int));
XElement payloadType = new XElement("PayloadType", typeof(string));
XElement request_msg = new XElement("Request_Message");
XElement req_type = new XElement("Request_Type", "Insert");
XElement key = new XElement("Key", 45);
XElement name = new XElement("Name", "element_one");
XElement descr = new XElement("Description", "Descr of element_one");
XElement payload = new XElement("Payload", "This the payload of element one.");
request_msg.Add(req_type);
request_msg.Add(key);
request_msg.Add(name);
request_msg.Add(descr);
request_msg.Add(payload);
Console.WriteLine("Message = \n{0}", request_msg.ToString());
XElement Rmsg = XElement.Parse(request_msg.ToString());
string Rtype = Rmsg.Element("Request_Type").Value;
Console.WriteLine("Request type = {0}", Rtype);
XElement abc = new XElement("dummy");
XElement result = new XElement("Result", "Success");
//Console.WriteLine("abc= {0}\nresult = {1}\n", abc.ToString(), result.ToString());
//abc = result;
Console.WriteLine("abc= {0}\nresult = {1}", abc.ToString(), result.ToString());
int k = 5;
string ts = "Could not find element with key " + k.ToString() + " in database";
//XElement tst = new XElement("Result", "Could not find element with key {0} in database", k);
XElement tst = new XElement("Result", ts);
Console.WriteLine("tst = {0}", tst.ToString());
XElement qry = new XElement("Query_Response");
XElement par = new XElement("Partial", "This is \njust payload");
qry.Add(tst);
qry.Add(par);
Console.WriteLine("qry = \n{0}", qry.ToString());
Console.WriteLine("value of qry response =\n{0}", qry.Value.ToString());
//noSqlDb.Add(keyType);
//noSqlDb.Add(payloadType);
//Console.WriteLine("\nString mesage = \n{0}", noSqlDb.ToString());
//string xml_string = noSqlDb.ToString();
//XElement abc = XElement.Parse(xml_string);
//XElement root = abc.Element("KeyType");
//Console.WriteLine("abc= {0}", abc.ToString());
//Console.WriteLine("root= {0}", root.ToString());
//elem.name = xml_dbElement.Element("Name").Value;
//string par = root.Value;
//Console.WriteLine("par = {0}", par);
}
