/// <summary>
/// Opens up a new connection with a given file.
/// At the file's location the connector also places the necessary library files.
/// </summary>
/// <param name="filename">The file which is storing the DB.</param>
/// <exception cref="Exception">Thrown if the connection is already open or an internal
/// library error occured while executing sqlite3_open().</exception>
/// <exception cref="ArgumentNullException">Thrown if the provided file name is
/// null or empty.</exception>
public void open(string filename)
{
if (this.IsOpen)
{
throw new Exception("DB connection is already open.");
}
this.filename = filename;
if (String.IsNullOrEmpty(filename))
{
throw new ArgumentNullException("filename", "The parameter is null or empty.");
}
try
{
SQLitePInvoke.installUnmanagedLib(Path.GetDirectoryName(filename));
if (SQLitePInvoke.sqlite3_open(this.filename, ref db) != SQLitePInvoke.SQLITE_OK)
{
throw new Exception("Error executing sqlite3_open()!");
}
this.IsOpen = true;
}
catch (Exception e)
{
this.db = IntPtr.Zero;
throw new Exception("Could not connect to DB.", e);
}
}
/// <summary>
/// Releases the unmanaged resources use by the SQLite3 and
/// optionally releases the managed resources.
/// </summary>
/// <param name="disposing">\c true to release both managed and
/// unmanaged resources; \c false to release only managed resources.
/// </param>
protected virtual void Dispose(bool disposing)
{
if (disposing) // release (un)managed resources
{
if (this.db != IntPtr.Zero)
{
SQLitePInvoke.sqlite3_close(this.db);
this.db = IntPtr.Zero;
this.IsOpen = false;
}
}
}
/// <summary>
/// Executes an SQL statemant on an opened connection. Before using
/// execute ensure that you have opened up the connection using the
/// open method. This method shell be used for data manipulation
/// statemants. If you'd like to query data use query().
/// </summary>
/// <param name="sql">The SQL statemant to execute.</param>
public void execute(string sql)
{
try
{
IntPtr errMsgPtr = IntPtr.Zero;
if (SQLitePInvoke.sqlite3_exec(db, sql, ref errMsgPtr) != SQLitePInvoke.SQLITE_OK)
{
var errMsg = System.Runtime.InteropServices.Marshal.PtrToStringAnsi(errMsgPtr);
SQLitePInvoke.sqlite3_free(errMsgPtr);
throw new Exception(
String.Format("Error executing sqlite3_exec() - {0}!", errMsg));
}
}
catch (Exception e)
{
throw new Exception("Could not execute SQL statement.", e);
}
}
/// <summary>
/// Execute a data query statemant (\c SELECT). This method differs from
/// execute() only in that it fills the LastQuery property. You may use
/// this method for data manipulation statemants as well but this would
/// clear the LastQuery property.
/// </summary>
/// <param name="sql">The sql statemant to query the database.</param>
public void query(string sql)
{
LastQuery = new List <Dictionary <string, string> >();
try
{
IntPtr errMsgPtr = IntPtr.Zero;
if (SQLitePInvoke.sqlite3_exec(db, sql, ref errMsgPtr, query)
!= SQLitePInvoke.SQLITE_OK)
{
var errMsg = Marshal.PtrToStringAnsi(errMsgPtr);
SQLitePInvoke.sqlite3_free(errMsgPtr);
throw new Exception(
String.Format("Error executing sqlite3_exec() - {0}!", errMsg));
}
}
catch (Exception e)
{
throw new Exception("Could not execute SQL statement.", e);
}
}