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// Copyright (C) 2004-2005 MySQL AB
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License version 2 as published by
// the Free Software Foundation
//
// There are special exceptions to the terms and conditions of the GPL
// as it is applied to this software. View the full text of the
// exception in file EXCEPTIONS in the directory of this software
// distribution.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
using System;
using System.Data;
using System.Collections.Specialized;
using System.Text;
using System.ComponentModel;
using System.Globalization;
using MySql.Data.Common;
namespace MySql.Data.MySqlClient
{
/// <include file='docs/MySqlConnection.xml' path='docs/ClassSummary/*'/>
[System.Drawing.ToolboxBitmap( typeof(MySqlConnection), "MySqlClient.resources.connection.bmp")]
[System.ComponentModel.DesignerCategory("Code")]
[ToolboxItem(true)]
public sealed class MySqlConnection : Component, IDbConnection, IDisposable, ICloneable
{
internal ConnectionState state;
internal Driver driver;
private MySqlDataReader dataReader;
private MySqlConnectionString settings;
private bool hasBeenOpen;
/// <include file='docs/MySqlConnection.xml' path='docs/StateChange/*'/>
public event StateChangeEventHandler StateChange;
/// <include file='docs/MySqlConnection.xml' path='docs/InfoMessage/*'/>
public event MySqlInfoMessageEventHandler InfoMessage;
/// <include file='docs/MySqlConnection.xml' path='docs/DefaultCtor/*'/>
public MySqlConnection()
{
//TODO: add event data to StateChange docs
settings = new MySqlConnectionString();
settings.LoadDefaultValues();
}
/// <include file='docs/MySqlConnection.xml' path='docs/Ctor1/*'/>
public MySqlConnection(string connectionString) : this()
{
ConnectionString = connectionString;
}
#region Interal Methods & Properties
internal MySqlConnectionString Settings
{
get { return settings; }
}
internal MySqlDataReader Reader
{
get { return dataReader; }
set { dataReader = value; }
}
internal char ParameterMarker
{
get { if (settings.UseOldSyntax) return '@'; return '?'; }
}
internal void OnInfoMessage( MySqlInfoMessageEventArgs args )
{
if (InfoMessage != null)
{
InfoMessage( this, args );
}
}
#endregion
#region Properties
/// <summary>
/// Returns the id of the server thread this connection is executing on
/// </summary>
[Browsable(false)]
public int ServerThread
{
get { return driver.ThreadID; }
}
/// <summary>
/// Gets the name of the MySQL server to which to connect.
/// </summary>
[Browsable(true)]
public string DataSource
{
get { return settings.Server; }
}
/// <include file='docs/MySqlConnection.xml' path='docs/ConnectionTimeout/*'/>
[Browsable(true)]
public int ConnectionTimeout
{
get { return settings.ConnectionTimeout; }
}
/// <include file='docs/MySqlConnection.xml' path='docs/Database/*'/>
[Browsable(true)]
public string Database
{
get { return settings.Database; }
}
/// <summary>
/// Indicates if this connection should use compression when communicating with the server.
/// </summary>
[Browsable(false)]
public bool UseCompression
{
get { return settings.UseCompression; }
}
/// <include file='docs/MySqlConnection.xml' path='docs/State/*'/>
[Browsable(false)]
public ConnectionState State
{
get { return state; }
}
/// <include file='docs/MySqlConnection.xml' path='docs/ServerVersion/*'/>
[Browsable(false)]
public string ServerVersion
{
get { return driver.Version.ToString(); }
}
internal Encoding Encoding
{
get
{
if (driver == null)
return System.Text.Encoding.Default;
else
return driver.Encoding;
}
}
/// <include file='docs/MySqlConnection.xml' path='docs/ConnectionString/*'/>
#if WINDOWS
[Editor("MySql.Data.MySqlClient.Design.ConnectionStringTypeEditor,MySqlClient.Design", typeof(System.Drawing.Design.UITypeEditor))]
#endif
[Browsable(true)]
[Category("Data")]
[Description("Information used to connect to a DataSource, such as 'Server=xxx;UserId=yyy;Password=zzz;Database=dbdb'.")]
public string ConnectionString
{
get
{
// Always return exactly what the user set.
// Security-sensitive information may be removed.
return settings.GetConnectionString(!hasBeenOpen);
}
set
{
if (this.State != ConnectionState.Closed)
throw new MySqlException("Not allowed to change the 'ConnectionString' property while the connection (state=" + State + ").");
settings.SetConnectionString(value);
if ( driver != null)
driver.Settings = settings;
}
}
#endregion
#region Transactions
/// <include file='docs/MySqlConnection.xml' path='docs/BeginTransaction/*'/>
public MySqlTransaction BeginTransaction()
{
return this.BeginTransaction( IsolationLevel.RepeatableRead );
}
IDbTransaction IDbConnection.BeginTransaction()
{
return BeginTransaction();
}
/// <include file='docs/MySqlConnection.xml' path='docs/BeginTransaction1/*'/>
public MySqlTransaction BeginTransaction(IsolationLevel iso)
{
//TODO: check note in help
if (state != ConnectionState.Open)
throw new InvalidOperationException(Resources.GetString("ConnectionNotOpen"));
MySqlTransaction t = new MySqlTransaction(this, iso);
MySqlCommand cmd = new MySqlCommand("", this);
cmd.CommandText = "SET SESSION TRANSACTION ISOLATION LEVEL ";
switch (iso)
{
case IsolationLevel.ReadCommitted:
cmd.CommandText += "READ COMMITTED"; break;
case IsolationLevel.ReadUncommitted:
cmd.CommandText += "READ UNCOMMITTED"; break;
case IsolationLevel.RepeatableRead:
cmd.CommandText += "REPEATABLE READ"; break;
case IsolationLevel.Serializable:
cmd.CommandText += "SERIALIZABLE"; break;
case IsolationLevel.Chaos:
throw new NotSupportedException(Resources.GetString("ChaosNotSupported"));
}
cmd.ExecuteNonQuery();
cmd.CommandText = "BEGIN";
cmd.ExecuteNonQuery();
return t;
}
IDbTransaction IDbConnection.BeginTransaction(IsolationLevel il)
{
return BeginTransaction(il);
}
#endregion
/// <include file='docs/MySqlConnection.xml' path='docs/ChangeDatabase/*'/>
public void ChangeDatabase(string databaseName)
{
if (databaseName == null || databaseName.Trim().Length == 0)
throw new ArgumentException(
Resources.GetString("ParameterIsInvalid"), "database");
if (state != ConnectionState.Open)
throw new InvalidOperationException(
Resources.GetString("ConnectionNotOpen"));
driver.SetDatabase(databaseName);
settings.Database = databaseName;
}
internal void SetState( ConnectionState newState )
{
ConnectionState oldState = state;
state = newState;
if (this.StateChange != null)
StateChange(this, new StateChangeEventArgs( oldState, newState ));
}
/// <summary>
/// Ping
/// </summary>
/// <returns></returns>
public bool Ping()
{
bool result = driver.Ping();
if (! result)
Terminate();
return result;
}
/// <include file='docs/MySqlConnection.xml' path='docs/Open/*'/>
public void Open()
{
if (state == ConnectionState.Open)
throw new InvalidOperationException(
Resources.GetString("ConnectionAlreadyOpen"));
SetState(ConnectionState.Connecting);
try
{
if (settings.Pooling)
{
driver = MySqlPoolManager.GetConnection(settings);
}
else
{
driver = Driver.Create(settings);
}
}
catch (Exception)
{
SetState(ConnectionState.Closed);
throw;
}
// if the user is using old syntax, let them know
if ( driver.Settings.UseOldSyntax)
Logger.LogWarning("You are using old syntax that will be removed in future versions");
SetState(ConnectionState.Open);
driver.Configure(this);
if (settings.Database != null && settings.Database.Length != 0)
ChangeDatabase(settings.Database);
hasBeenOpen = true;
}
internal void Terminate()
{
try
{
if (settings.Pooling)
MySqlPoolManager.ReleaseConnection(driver);
else
driver.Close();
}
catch (Exception) { }
SetState(ConnectionState.Closed);
}
/// <include file='docs/MySqlConnection.xml' path='docs/Close/*'/>
public void Close()
{
//TODO: rollback any pending transaction
if (state == ConnectionState.Closed) return;
if (dataReader != null)
dataReader.Close();
Terminate();
}
IDbCommand IDbConnection.CreateCommand()
{
return CreateCommand();
}
/// <include file='docs/MySqlConnection.xml' path='docs/CreateCommand/*'/>
public MySqlCommand CreateCommand()
{
// Return a new instance of a command object.
MySqlCommand c = new MySqlCommand();
c.Connection = this;
return c;
}
#region ICloneable
/// <summary>
/// Creates a new MySqlConnection object with the exact same ConnectionString value
/// </summary>
/// <returns>A cloned MySqlConnection object</returns>
object ICloneable.Clone()
{
MySqlConnection clone = new MySqlConnection();
clone.ConnectionString = this.ConnectionString;
//TODO: how deep should this go?
return clone;
}
#endregion
#region IDisposeable
/// <summary>
/// Releases the resources used by the MySqlConnection.
/// </summary>
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (State == ConnectionState.Open)
Close();
}
base.Dispose(disposing);
}
#endregion
}
/// <summary>
/// Represents the method that will handle the <see cref="MySqlConnection.InfoMessage"/> event of a
/// <see cref="MySqlConnection"/>.
/// </summary>
public delegate void MySqlInfoMessageEventHandler(object sender, MySqlInfoMessageEventArgs args);
/// <summary>
/// Provides data for the InfoMessage event. This class cannot be inherited.
/// </summary>
public class MySqlInfoMessageEventArgs : EventArgs
{
/// <summary>
///
/// </summary>
public MySqlError[] errors;
}
}
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