The Using Statement

The Using statement is used to get a resource, execute a embedded statement block and then release the resource.

using-statement:

Using identifier := expression Do block End Using

The structure or class implementing the System.IDisposable interface, is named a resource. This interface has a single parameterless method named Dispose. A code using the resource can call the Dispose method to indicate that this resource is no longer required.

The Using structure is expanded as follows:

Begin

identifier := expression;

Try

block

Finally

If identifier <> Null Then

(identifier as IDisposable).Dispose;

End If

End Try

End

Example

Private Sub TestUsing();
Var
    a: Font;
Begin
    Using a := New Font("Arial", 10) Do
        //Using obtained font
    End Using;
End Sub;