Memanggil Oracle Procedure dengan C#

Memanggil Oracle Procedure dengan C#

FUNCTION CheckExistNews(newsurl IN VARCHAR2) RETURN NUMBER AS
checkvalue NUMBER;
BEGIN

SELECT COUNT(*) INTO checkvalue
FROM InfoRetrieved where InfoRetrieved.URL=newsurl;
RETURN checkvalue;
END;

C# function :

public bool CheckExistNews(string url)
{
bool ret = false;
int ok=0;
OracleCommand myCommand = new OracleCommand("PKG_Test.CheckExistNews", connection);
myCommand.CommandType = CommandType.StoredProcedure;
myCommand.Parameters.Add(new OracleParameter("newsurl", OracleType.VarChar, 500));
myCommand.Parameters["newsurl"].Value = url;
myCommand.Parameters.Add(new OracleParameter("checkvalue", OracleType.Number,1));
myCommand.Parameters["checkvalue"].Direction = ParameterDirection.ReturnValue;

try
{
if(connection.State!= ConnectionState.Open)
connection.Open();
myCommand.ExecuteScalar();
ok=Convert.ToInt32(myCommand.Parameters["checkvalue"].Value);
if (ok!=0)
ret = true;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"CheckExistNews : Error");
}
finally
{
connection.Close();
}
return ret;
}