/// <include file='doc\OleDbTransaction.uex' path='docs/doc[@for="OleDbTransaction.Begin"]/*' />
public OleDbTransaction Begin(IsolationLevel isolevel)
{
OleDbConnection.OleDbPermission.Demand(); // MDAC 81476
if (null == this.localTransaction)
{
throw ADP.TransactionZombied(this);
}
parentConnection.CheckStateOpen(ADP.BeginTransaction);
OleDbTransaction transaction = new OleDbTransaction(this.parentConnection);
this.weakTransaction = new WeakReference(transaction);
transaction.BeginInternal(this.localTransaction, isolevel);
transaction.parentTransaction = this;
return(transaction);
}
private bool PropertiesOnCommand(bool throwNotSupported)
{
if (null != _icommandText)
{
return(true);
}
Debug.Assert(!_isPrepared, "null command isPrepared");
OleDbConnection connection = _connection;
if (null == connection)
{
connection.CheckStateOpen(ODB.Properties);
}
if (!_trackingForClose)
{
_trackingForClose = true;
connection.AddWeakReference(this, OleDbReferenceCollection.CommandTag);
}
_icommandText = connection.ICommandText();
if (null == _icommandText)
{
if (throwNotSupported || HasParameters())
{
throw ODB.CommandTextNotSupported(connection.Provider, null);
}
return(false);
}
using (DBPropSet propSet = CommandPropertySets())
{
if (null != propSet)
{
UnsafeNativeMethods.ICommandProperties icommandProperties = ICommandProperties();
OleDbHResult hr = icommandProperties.SetProperties(propSet.PropertySetCount, propSet);
if (hr < 0)
{
SafeNativeMethods.Wrapper.ClearErrorInfo();
}
}
}
return(true);
}
private void ValidateConnection(string method)
{
if (null == _connection)
{
throw ADP.ConnectionRequired(method);
}
_connection.CheckStateOpen(method);
// user attempting to execute the command while the first dataReader hasn't returned
// use the connection reference collection to see if the dataReader referencing this
// command has been garbage collected or not.
if (_hasDataReader)
{
if (_connection.HasLiveReader(this))
{
throw ADP.OpenReaderExists();
}
_hasDataReader = false;
}
}
private bool PropertiesOnCommand(bool throwNotSupported)
{
if (this._icommandText == null)
{
OleDbConnection connection = this._connection;
if (connection == null)
{
connection.CheckStateOpen("Properties");
}
if (!this._trackingForClose)
{
this._trackingForClose = true;
connection.AddWeakReference(this, 1);
}
this._icommandText = connection.ICommandText();
if (this._icommandText == null)
{
if (throwNotSupported || this.HasParameters())
{
throw ODB.CommandTextNotSupported(connection.Provider, null);
}
return(false);
}
using (DBPropSet set = this.CommandPropertySets())
{
if (set != null)
{
System.Data.Common.UnsafeNativeMethods.ICommandProperties properties = this.ICommandProperties();
Bid.Trace("<oledb.ICommandProperties.SetProperties|API|OLEDB> %d#\n", this.ObjectID);
OleDbHResult result = properties.SetProperties(set.PropertySetCount, set);
Bid.Trace("<oledb.ICommandProperties.SetProperties|API|OLEDB|RET> %08X{HRESULT}\n", result);
if (result < OleDbHResult.S_OK)
{
SafeNativeMethods.Wrapper.ClearErrorInfo();
}
}
}
}
return(true);
}
