What is a standard way of declaring constants?

[leok31]

I know that a public constant is available to all subs and modules (hope thats right). I also know that you can only declare these in a module, you can't for example declare these in the form.
So how what is the best way of declaring them?
At the moment I just have a module that has nothing else except for the 3-4 constants that I use throughout all my forms. Is that ok?

thanks

 

[Uncle Gizmo]

Yes, that sounds fine...

Are the constants related in any way?

 

[leok31]

thanks.
no they are not. I have a few strings that I want to use throughout the project and I want to set up the connection string there as well. I connect to SQL server many times and at the moment i keep on repeating the code on each connection.
It gets tedious when I need to make a small change to the connections.

 

[Galaxiom]

I connect to SQL server many times and at the moment i keep on repeating the code on each connection.

Put the connection creation code into function in a Standard Module. Return a connection object.

Note however that the same connection can be shared. The connection can be stored as a Global variable. When using multiple connections I store them in a Collection (or more often a Dictionary because the index can be searched).

Test the State of the connection each time it is used in case it is closed and simply open it again if necessary.

 

[leok31]

thanks for that.
I don't think I understand how the global variable works.
So I understand that you can declare it once for the whole project, for example
Public strABC as string.
How I can use this variable everywhere without declaring it again.
But if I set it as something, for example
strABC = "Hello World", that doesn't seem to work.
So why would I use a Global Variable instead of a Constant?

I hope my question makes sense.

 

[Galaxiom]

The key word in variables is "scope". It defines where a variable can be seen from.

A Public variable declared in the declarations section at the top of a Standard Module has a global scope. It exists for the whole time the application is open and is available across the whole project. Simply refer to its name.

A Public variable in the declarations section of a Class module (including Access Object Modules) is available to the project via the object.

eg From the project to a variable in a Form module: Forms!formname.variablename

A Private variable in the declarations section is available throughout the module. It exists while the module's object is open.

Variables dimmed inside a function or sub are only available to that function or sub.

Use variables instead of constants for objects such as a Connection. They can't be declared as constants.