/// --------------------------------------------------------------------------------
/// <summary>
/// Provides a means by which to ensure all locks have been removed for this user
/// in situations where an unexpected exception occurs and/or the user logs out of
/// system.
/// </summary>
/// --------------------------------------------------------------------------------
public void UnlockAll()
{
SQL.SQLDelete objDelete = new SQL.SQLDelete();
objDelete.TableName = pstrLockTableName;
objDelete.Where.Add("UserID", SQL.ComparisonOperator.EqualTo, pstrCurrentUserID);
using (ConnectionScope connection = new ConnectionScope(pobjDatabase))
connection.ExecuteNonQuery(objDelete);
}
/// --------------------------------------------------------------------------------
/// <summary>
/// Deletes an object's database record. If the collection's IDatabaseObjects.Subset
/// has been implemented then the object must exist within the subset, otherwise the
/// object will not be deleted. If the object has not been saved to the database the
/// function will exit without executing an SQL DELETE command. After deleting the
/// database record the object is set to Nothing. The calling function should receive
/// the object ByRef for this to have any affect. Setting the object to Nothing
/// minimises the possibility of the deleted object being used in code after
/// ObjectDelete has been called.
/// </summary>
///
/// <param name="objCollection">
/// The collection that contains the object to delete. If the item does not exist
/// within the collection then the object will not be deleted.
/// </param>
///
/// <param name="objItem">
/// The object to delete. The calling function should receive this object ByRef
/// as the object is set to Nothing after deletion.
/// Reference Type: <see cref="IDatabaseObject" /> (DatabaseObjects.IDatabaseObject)
/// </param>
///
/// <example>
/// <code>
/// Public Sub Delete(ByRef objProduct As Product)
///
/// objDatabase.ObjectDelete(Me, objProduct)
/// 'objProduct will now be Nothing
///
/// End Sub
/// </code>
/// </example>
/// --------------------------------------------------------------------------------
///
public void ObjectDelete(IDatabaseObjects objCollection, ref IDatabaseObject objItem)
{
if (objItem.IsSaved)
{
SQL.SQLDelete objDelete = new SQL.SQLDelete();
SQL.SQLConditions objSubset;
objDelete.TableName = objCollection.TableName();
objDelete.Where.Add(objCollection.DistinctFieldName(), SQL.ComparisonOperator.EqualTo, objItem.DistinctValue);
objSubset = objCollection.Subset();
if (objSubset != null && !objSubset.IsEmpty)
objDelete.Where.Add(objSubset);
using (ConnectionScope objConnection = new ConnectionScope(this))
objConnection.ExecuteNonQuery(objDelete);
objItem.IsSaved = false;
if (Transaction.Current != null)
{
IDatabaseObject objItemCopy = objItem;
Transaction.Current.EnlistVolatile(new TransactionExecuteActionOnRollback(() => objItemCopy.IsSaved = true), EnlistmentOptions.None);
}
}
//The function that calls ObjectDelete objItem MUST be ByRef for this to have any effect
objItem = null;
}
/// --------------------------------------------------------------------------------
/// <summary>
/// UnLocks this object. Throws an exception if the object is not locked by the current
/// user or the object has not been saved.
/// </summary>
/// --------------------------------------------------------------------------------
public void UnLock(IDatabaseObjects objCollection, IDatabaseObject objObject)
{
//If the table is locked by someone else
if (!this.IsLockedByCurrentUser(objCollection, objObject))
throw new MethodAccessException("Object already locked");
else if (!objObject.IsSaved)
throw new MethodAccessException("Object is not saved and cannot be unlocked");
SQL.SQLDelete objDelete = new SQL.SQLDelete();
objDelete.TableName = pstrLockTableName;
objDelete.Where.Add("TableName", SQL.ComparisonOperator.EqualTo, objCollection.TableName());
objDelete.Where.Add("RecordID", SQL.ComparisonOperator.EqualTo, objObject.DistinctValue.ToString());
objDelete.Where.Add("UserID", SQL.ComparisonOperator.EqualTo, pstrCurrentUserID);
using (ConnectionScope connection = new ConnectionScope(pobjDatabase))
connection.ExecuteNonQuery(objDelete);
}
/// --------------------------------------------------------------------------------
/// <summary>
/// Deletes all of the objects in the collection. If IDatabaseObjects.Subset
/// has been implemented then only the objects within the subset are deleted, not
/// the table's entire contents.
/// </summary>
///
/// <param name="objCollection">
/// The collection from which all objects are to be deleted.
/// </param>
/// --------------------------------------------------------------------------------
///
public void ObjectsDeleteAll(IDatabaseObjects objCollection)
{
SQL.SQLDelete objDelete = new SQL.SQLDelete();
objDelete.TableName = objCollection.TableName();
objDelete.Where = objCollection.Subset();
using (ConnectionScope objConnection = new ConnectionScope(this))
objConnection.ExecuteNonQuery(objDelete);
}