The template enables you to create Singleton classes in VBA and enjoy the convenience of calling it by its name without requiring to create an instance.

NOTE: Do not copy and paste directly into VBA! This will not compile; import it as a .cls file instead. Once imported, you can copy/paste the module itself and retain the appropriate class properties to use it as a singleton.

This must be copied into a text document, saved as a .cls file and use VBA Editor's Import file to import the file. This is the only way to process the attributes that are not exposed via VBA editor. We have to do this way because we modified an attribute, "VB_PredeclaredId" to be true. This enables you to call it by name as such.

Thus, instead of the conventional instancing:

We can do this instead:

The Singleton also will throw an error if someone attempt to create a new instance of Singleton and thus block. This is primarily meant to be a self-documenting tool to remind the developers of the intended uses.

Notes on Initialization and Termination of Singleton Classes

The Singleton Class will Initialize only once, which happens on the first call to a class method or property. However, the Termination method of the class does not execute even as Access shuts down. To make use of a deconstructor for the class, you must write your own public method and call it from your Access shutdown code.

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