Object Error Posts

Run-time error '3709':
Operation is not allowed on an object referencing a closed or invalid connection.

A.k.a. Class Contract and Design by Contracts.

A contract with a method that must be true upon calling (pre) or exiting (post). A pre-condition contract must be true when the method is called. A post-condition contract must be true when exiting. If either are not true, an error is raised. For example, you can use code contracts to check for the validity of input parameters, and results

An invariant is also a code contract which validates the state of the object required by the method.

To refer to the current instance of a class or structure, use the Me keyword. Me provides a way to refer to the specific instance in which the code is currently executing. It is particularly useful for passing information about the currently executing instance.

The Me keyword is also used as a modifier of the first parameter of an extension method.

You cannot use Me with static method functions because static methods do not belong to an object instance. If you try, you'll get an error.

To refer to the current instance of a class, use the this keyword. The this keyword provides a way to refer to the specific instance in which the code is currently executing. It is particularly useful for passing information about the currently executing instance.

The this keyword is also used as a modifier of the first parameter of an extension method.

You cannot use this with static method functions because static methods do not belong to an object instance. If you try, you'll get an error.

Within the implementation of a method, the identifier Self references the object in which the method is called. The Self variable is an implicit parameter for each object method.
A method can use this variable to refer to its owning class.