Enumeration Class Woe

Getting Started
1

So I have tried to search the forum for help and find that I’m perhaps not the only person that has struggled a bit with Enumerations. I have perhaps misunderstood scope of usage but if I may, let me explain what I am trying to do…

I have a class (clsDBConn) that I am developing that handles database connectivity and will allow the creation and management of multiple concurrent recordsets. I have an enumeration called ConnType in the class and it is populated with MySQL,SQLite,SQLServer. I have a property in the class called DatabaseType which is declared with a type of ConnType.

I want to be able to identify which database type the instance of the class is connecting to as there are some nuances between databases that I need to handle in code. There will be more entries in the Enumeration in due course, these 3 are for initial testing.

In my main code I instantiate the class as DBConn and I set some other properties like DBName, User Password etc. and I have a line of code which is:

DBConn.DatabaseType = DBConn.ConnType.MySQL

The IDE happily sees all of this and will allow tab to autocomplete

I get a compile time error:

Type “clsDBConn” has no member named MySQL
DBConn.DatabaseType = DBConn.ConnType.MySQL (MySQL on this line is highlighted in Yellow)

I had thought that perhaps the scope was not right so I created a new property as a test (DoIt) also declared as ConnType and tried to assign DBConn.DatabaseType with DoIt.MySQL but I get a similar error.

I do know that I can achieve what I want using constants and if I use the Enumeration within a Method, it also works fine so am I simply trying to get the class to do something that Xojo does not like which can only be picked up at compile time?

I also know that if I strip out this code and simply assume that the Database is MySQL, the code works and can pull back the recordsets with no problems. So my issue is with how I am attempting to use the Enumeration. Putting the Enumeration into a Module does not feel right as it is integral to this class.

Thanks in advance,

Mark

2

When using an enum that’s defined in a class use the class super rather than the instance of when using the enum values.

DBConn.DatabaseType = clsDBConn.ConnType.MySQL

See if that works :slight_smile:

3

I was going to reply, but Tim beat me to it. Do what he said.

4

Doh! (Slaps Forehead).

That worked perfectly, one of those cannae see the wood for the trees moments.

Thank you gents, one happy camper here :slight_smile:

Mark

5

[quote=399593:@Tim Parnell]When using an enum that’s defined in a class use the class super rather than the instance of when using the enum values.

DBConn.DatabaseType = clsDBConn.ConnType.MySQL

[/quote]
I’ve regularly asked myself why the enumeration won’t work from an instance… Instances also know their enumerations, after all.