/// <summary>
/// Simplify the creation of a TurboDB command object by allowing
/// a CommandType and Command Text to be provided
/// </summary>
/// <remarks>
/// e.g.:
/// TurboDBCommand command = CreateCommand(conn, CommandType.Text, "Select * from Customers");
/// </remarks>
/// <param name="connection">A valid TurboDBConnection object</param>
/// <param name="commandType">CommandType (TableDirect, Text)</param>
/// <param name="commandText">CommandText</param>
/// <returns>A valid TurboDBCommand object</returns>
public static TurboDBCommand CreateCommand(TurboDBConnection connection, CommandType commandType, string commandText )
{
if( connection == null ) throw new ArgumentNullException( "connection" );
if( commandType == CommandType.StoredProcedure ) throw new ArgumentException("Stored Procedures are not supported.");
// If we receive parameter values, we need to figure out where they go
if ((commandText == null) && (commandText.Length<= 0)) throw new ArgumentNullException( "Command Text" );
// Create a TurboDBCommand
TurboDBCommand cmd = new TurboDBCommand(commandText, connection );
cmd.CommandType = CommandType.Text ;
return cmd;
}
/// <summary>
/// Create and prepare a TurboDBCommand, and call ExecuteReader with the appropriate CommandBehavior.
/// </summary>
/// <remarks>
/// If we created and opened the connection, we want the connection to be closed when the DataReader is closed.
///
/// If the caller provided the connection, we want to leave it to them to manage.
/// </remarks>
/// <param name="connection">A valid TurboDBConnection, on which to execute this command</param>
/// <param name="transaction">A valid TurboDBTransaction, or 'null'</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="commandParameters">An array of TurboDBParameters to be associated with the command or 'null' if no parameters are required</param>
/// <param name="connectionOwnership">Indicates whether the connection parameter was provided by the caller, or created by TurboDBHelper</param>
/// <returns>TurboDBDataReader containing the results of the command</returns>
private static TurboDBDataReader ExecuteReader(TurboDBConnection connection, TurboDBTransaction transaction, CommandType commandType, string commandText, TurboDBParameter[] commandParameters, TurboDBConnectionOwnership connectionOwnership)
{
if( connection == null ) throw new ArgumentNullException( "connection" );
bool mustCloseConnection = false;
// Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
try
{
PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
// Create a reader
TurboDBDataReader dataReader;
// Call ExecuteReader with the appropriate CommandBehavior
if (connectionOwnership == TurboDBConnectionOwnership.External)
{
dataReader = cmd.ExecuteReader();
}
else
{
dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
// Detach the TurboDBParameters from the command object, so they can be used again.
// HACK: There is a problem here, the output parameter values are fletched
// when the reader is closed, so if the parameters are detached from the command
// then the TurboDBReader can´t set its values.
// When this happen, the parameters can´t be used again in other command.
bool canClear = true;
foreach(TurboDBParameter commandParameter in cmd.Parameters)
{
if (commandParameter.Direction != ParameterDirection.Input)
canClear = false;
}
if (canClear)
{
cmd.Parameters.Clear();
}
return dataReader;
}
catch
{
if( mustCloseConnection )
connection.Close();
throw;
}
}
/// <summary>
/// This method is used to attach array of TurboDBParameters to a TurboDBCommand.
///
/// This method will assign a value of DbNull to any parameter with a direction of
/// InputOutput and a value of null.
///
/// This behavior will prevent default values from being used, but
/// this will be the less common case than an intended pure output parameter (derived as InputOutput)
/// where the user provided no input value.
/// </summary>
/// <param name="command">The command to which the parameters will be added</param>
/// <param name="commandParameters">An array of TurboDBParameters to be added to command</param>
private static void AttachParameters(TurboDBCommand command, TurboDBParameter[] commandParameters)
{
if( command == null ) throw new ArgumentNullException( "command" );
if( commandParameters != null )
{
foreach (TurboDBParameter p in commandParameters)
{
if( p != null )
{
// Check for derived output value with no value assigned
if ( ( p.Direction == ParameterDirection.InputOutput ||
p.Direction == ParameterDirection.Input ) &&
(p.Value == null))
{
p.Value = DBNull.Value;
}
command.Parameters.Add(p);
}
}
}
}
/// <summary>
/// Executes the respective command for each inserted, updated, or deleted row in the DataSet.
/// </summary>
/// <remarks>
/// e.g.:
/// UpdateDataset(conn, insertCommand, deleteCommand, updateCommand, dataSet, "Order");
/// </remarks>
/// <param name="insertCommand">A valid transact-SQL statement to insert new records into the data source</param>
/// <param name="deleteCommand">A valid transact-SQL statement to delete records from the data source</param>
/// <param name="updateCommand">A valid transact-SQL statement used to update records in the data source</param>
/// <param name="dataSet">The DataSet used to update the data source</param>
/// <param name="tableName">The DataTable used to update the data source.</param>
public static void UpdateDataset(TurboDBCommand insertCommand, TurboDBCommand deleteCommand, TurboDBCommand updateCommand, DataSet dataSet, string tableName)
{
if( insertCommand == null ) throw new ArgumentNullException( "insertCommand" );
if( deleteCommand == null ) throw new ArgumentNullException( "deleteCommand" );
if( updateCommand == null ) throw new ArgumentNullException( "updateCommand" );
if( tableName == null || tableName.Length == 0 ) throw new ArgumentNullException( "tableName" );
// Create a TurboDBDataAdapter, and dispose of it after we are done
TurboDBDataAdapter dataAdapter = new TurboDBDataAdapter();
try
{
// Set the data adapter commands
dataAdapter.UpdateCommand = updateCommand;
dataAdapter.InsertCommand = insertCommand;
dataAdapter.DeleteCommand = deleteCommand;
// Update the dataset changes in the data source
dataAdapter.Update (dataSet,tableName);
// Commit all the changes made to the DataSet
dataSet.AcceptChanges();
}
catch (TurboDBException E)
{string strError=E.Message;}
finally{dataAdapter.Dispose();}
}
/// <summary>
/// Execute a TurboDBCommand (that returns a resultset) against the specified TurboDBTransaction
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// XmlReader r = ExecuteXmlReader(trans, CommandType.Text, "Select * from TableTransaction where ProdId=?", new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">A valid TurboDBTransaction</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command using "FOR XML AUTO"</param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
/// <returns>An XmlReader containing the resultset generated by the command</returns>
public static string ExecuteXml(TurboDBTransaction transaction, CommandType commandType, string commandText, params TurboDBParameter[] commandParameters)
{
if( transaction == null ) throw new ArgumentNullException( "transaction" );
if( transaction != null && transaction.Connection == null ) throw new ArgumentException( "The transaction was rollbacked or commited, please provide an open transaction.", "transaction" );
// // Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, (TurboDBConnection)transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// Create the DataAdapter & DataSet
TurboDBDataAdapter obj_Adapter =new TurboDBDataAdapter (cmd);
DataSet ds=new DataSet();
ds.Locale =CultureInfo.InvariantCulture;
obj_Adapter.Fill(ds);
// Detach the TurboDBParameters from the command object, so they can be used again
cmd.Parameters.Clear();
string retval= ds.GetXml();
ds.Clear();
obj_Adapter.Dispose ();
return retval;
}
/// <summary>
/// Execute a TurboDBCommand (that returns a resultset) against the specified TurboDBConnection
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// string r = ExecuteXml(conn, CommandType.Text, "Select * from TableTransaction where ProdId=?", new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">A valid TurboDBConnection</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command using "FOR XML AUTO"</param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
/// <returns>An string containing the resultset generated by the command</returns>
public static string ExecuteXml(TurboDBConnection connection, CommandType commandType, string commandText, params TurboDBParameter[] commandParameters)
{
if( connection == null ) throw new ArgumentNullException( "connection" );
bool mustCloseConnection = false;
// Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
try
{
PrepareCommand(cmd, connection, (TurboDBTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );
// Create the DataAdapter & DataSet
TurboDBDataAdapter obj_Adapter =new TurboDBDataAdapter (cmd);
DataSet ds=new DataSet();
ds.Locale =CultureInfo.InvariantCulture;
obj_Adapter.Fill(ds);
// Detach the TurboDBParameters from the command object, so they can be used again
cmd.Parameters.Clear();
string retval= ds.GetXml();
ds.Clear();
obj_Adapter.Dispose ();
return retval;
}
catch
{
if( mustCloseConnection )
connection.Close();
throw;
}
}
/// <summary>
/// Execute a TurboDBCommand (that returns a 1x1 resultset) against the specified TurboDBTransaction
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// int orderCount = (int)ExecuteScalar(trans, CommandType.Text, "Select count(Order) from TableTransaction where ProdId=?", new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">A valid TurboDBTransaction</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
/// <returns>An object containing the value in the 1x1 resultset generated by the command</returns>
public static object ExecuteScalar(TurboDBTransaction transaction, CommandType commandType, string commandText, params TurboDBParameter[] commandParameters)
{
if( transaction == null ) throw new ArgumentNullException( "transaction" );
if( transaction != null && transaction.Connection == null ) throw new ArgumentException( "The transaction was rollbacked or commited, please provide an open transaction.", "transaction" );
// Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, (TurboDBConnection)transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// Execute the command & return the results
object retval = cmd.ExecuteScalar();
// Detach the TurboDBParameters from the command object, so they can be used again
cmd.Parameters.Clear();
return retval;
}
/// <summary>
/// Execute a TurboDBCommand (that returns a 1x1 resultset) against the specified TurboDBConnection
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// int orderCount = (int)ExecuteScalar(conn, CommandType.Text, "Select count(Order) from TableTransaction where ProdId=?", new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">A valid TurboDBConnection</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
/// <returns>An object containing the value in the 1x1 resultset generated by the command</returns>
public static object ExecuteScalar(TurboDBConnection connection, CommandType commandType, string commandText, params TurboDBParameter[] commandParameters)
{
if( connection == null ) throw new ArgumentNullException( "connection" );
// Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, connection, (TurboDBTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );
// Execute the command & return the results
object retval = cmd.ExecuteScalar();
// Detach the TurboDBParameters from the command object, so they can be used again
cmd.Parameters.Clear();
if( mustCloseConnection )
connection.Close();
return retval;
}
/// <summary>
/// Execute a TurboDBCommand (that returns a resultset) against the specified TurboDBTransaction
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// DataSet ds = ExecuteDataset(trans, CommandType.Text, "Select * from TableTransaction where ProdId=?", new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">A valid TurboDBTransaction</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
/// <returns>A dataset containing the resultset generated by the command</returns>
public static DataSet ExecuteDataset(TurboDBTransaction transaction, CommandType commandType, string commandText, params TurboDBParameter[] commandParameters)
{
if( transaction == null ) throw new ArgumentNullException( "transaction" );
if( transaction != null && transaction.Connection == null ) throw new ArgumentException( "The transaction was rollbacked or commited, please provide an open transaction.", "transaction" );
// Create a command and prepare it for execution
TurboDBCommand cmd = new TurboDBCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, (TurboDBConnection)transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// Create the DataAdapter & DataSet
//using( TurboDBDataAdapter da = new TurboDBDataAdapter(cmd) )
TurboDBDataAdapter da = new TurboDBDataAdapter(cmd);
DataSet ds = new DataSet();
ds.Locale =CultureInfo.InvariantCulture;
// Fill the DataSet using default values for DataTable names, etc
da.Fill(ds);
// Detach the TurboDBParameters from the command object, so they can be used again
cmd.Parameters.Clear();
// Return the dataset
return ds;
}
/// <summary>
/// This method opens (if necessary) and assigns a connection, transaction, command type and parameters
/// to the provided command
/// </summary>
/// <param name="command">The TurboDBCommand to be prepared</param>
/// <param name="connection">A valid TurboDBConnection, on which to execute this command</param>
/// <param name="transaction">A valid TurboDBTransaction, or 'null'</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="commandParameters">An array of TurboDBParameters to be associated with the command or 'null' if no parameters are required</param>
/// <param name="mustCloseConnection"><c>true</c> if the connection was opened by the method, otherwose is false.</param>
private static void PrepareCommand(TurboDBCommand command, TurboDBConnection connection, TurboDBTransaction transaction, CommandType commandType, string commandText, TurboDBParameter[] commandParameters, out bool mustCloseConnection )
{
if( command == null ) throw new ArgumentNullException( "command" );
if(commandType == CommandType.StoredProcedure ) throw new ArgumentException("Stored Procedures are not supported.");
// If the provided connection is not open, we will open it
if (connection.State != ConnectionState.Open)
{
mustCloseConnection = true;
connection.Open();
}
else
{
mustCloseConnection = false;
}
// Associate the connection with the command
command.Connection = connection;
// Set the command text (SQL statement)
command.CommandText = commandText;
// If we were provided a transaction, assign it
if (transaction != null)
{
if( transaction.Connection == null ) throw new ArgumentException( "The transaction was rollbacked or commited, please provide an open transaction.", "transaction" );
command.Transaction = transaction;
}
// Set the command type
command.CommandType = commandType;
// Attach the command parameters if they are provided
if (commandParameters != null)
{
AttachParameters(command, commandParameters);
}
return;
}
/// <summary>
/// Private helper method that execute a TurboDBCommand (that returns a resultset) against the specified TurboDBTransaction and TurboDBConnection
/// using the provided parameters.
/// </summary>
/// <remarks>
/// e.g.:
/// FillDataset(conn, trans, CommandType.Text, "Select * from TableTransaction where ProdId=?", ds, new string[] {"orders"}, new TurboDBParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">A valid TurboDBConnection</param>
/// <param name="transaction">A valid TurboDBTransaction</param>
/// <param name="commandType">The CommandType (TableDirect, Text)</param>
/// <param name="commandText">The T-SQL command</param>
/// <param name="dataSet">A dataset wich will contain the resultset generated by the command</param>
/// <param name="tableNames">This array will be used to create table mappings allowing the DataTables to be referenced
/// by a user defined name (probably the actual table name)
/// </param>
/// <param name="commandParameters">An array of TurboDBParamters used to execute the command</param>
private static void FillDataset(TurboDBConnection connection, TurboDBTransaction transaction, CommandType commandType,
string commandText, DataSet dataSet, string[] tableNames,
params TurboDBParameter[] commandParameters)
{
if( connection == null ) throw new ArgumentNullException( "connection" );
if( dataSet == null ) throw new ArgumentNullException( "dataSet" );
// Create a command and prepare it for execution
TurboDBCommand command = new TurboDBCommand();
bool mustCloseConnection = false;
PrepareCommand(command, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
// Create the DataAdapter & DataSet
TurboDBDataAdapter dataAdapter = new TurboDBDataAdapter(command);
try
{
// Add the table mappings specified by the user
if (tableNames != null && tableNames.Length > 0)
{
string tableName = "Table";
for (int index=0; index < tableNames.Length; index++)
{
if( tableNames[index] == null || tableNames[index].Length == 0 ) throw new ArgumentException( "The tableNames parameter must contain a list of tables, a value was provided as null or empty string.", "tableNames" );
dataAdapter.TableMappings.Add(tableName, tableNames[index]);
tableName += (index + 1).ToString();
}
}
// Fill the DataSet using default values for DataTable names, etc
dataAdapter.Fill(dataSet);
// Detach the TurboDBParameters from the command object, so they can be used again
command.Parameters.Clear();
if( mustCloseConnection )
connection.Close();
}
finally
{
dataAdapter.Dispose();
}
}