/// <summary>
/// Removes Book object in the argument from database context and local memory collection.
/// Raises <event>OnDatabaseError</event> when exception is caught from attempting to change the database context.
/// </summary>
/// <param name="b">Book object to be removed</param>
/// <returns>returns true if operation is successful, false otherwise.</returns>
public bool RemoveBook(Book b)
{
if (!IsLibrarian)
{
return(false); //return false if IsLibrarian is false.
}
if (b.IsCheckedOut) //check if books are checked out or not
{
OnDatabaseErrorRaised(new DatabaseEventArgs("Cannot remove book, all copies must be checked in"));
return(false);
}
else //books are all checked in
{
try
{
//remove from database
context.Books.Remove(b);
context.SaveChanges();
}
catch (Exception ex)
{
while (ex != null)
{
ex = ex.InnerException;
}
DatabaseEventArgs e = new DatabaseEventArgs(ex.Message);
OnDatabaseErrorRaised(e);
return(false);
}
//remove from memory
bookInventory.Remove(b);
return(true);
}
}
