Can I set expressions programmatically?

I'm building SSIS packages through code and I would like to set the properties of some custom tasks (not data flow tasks) to expressions. I've done some searches but turned up nothing. This is the only thing I'm hitting a brick wall on at the moment; Books Online has been excellent in detailing how to create packages via code up to this point.

For the sake of argument, let's say I want to set the SqlStatementSource property of an Execute SQL task to this value:

"INSERT INTO [SomeTable] VALUES (NEWID(), '" + @.[User:omeStringVariable] + "')"

What would the code look like?

TaskHost has a SetExpression method:

TaskHost.SetExpression Method

http://msdn2.microsoft.com/de-de/library/microsoft.sqlserver.dts.runtime.taskhost.setexpression.aspx

I presume all of the other container types (Package, Sequence etc..) will do too.

-Jamie

|||AAAGGGGHHH!! I was expecting a property, not a method! So then in order to retrieve all expressions on a task, you'd have to iterate the Properties collection and call GetExpression() with the name of each one to see if it's non-null. Doesn't seem like a particularly good design to me. Why not a simple collection? Oh well, thanks for the help.|||

JeffJohnsonMVPVB wrote:

AAAGGGGHHH!! I was expecting a property, not a method! So then in order to retrieve all expressions on a task, you'd have to iterate the Properties collection and call GetExpression() with the name of each one to see if it's non-null. Doesn't seem like a particularly good design to me. Why not a simple collection? Oh well, thanks for the help.

Yep. I was expecting a Collection as well.

Maybe a read-only collection would be nice that is populated by SetExpression(). Are there such things as read-only collections? I've no idea - I'm no developer.

I too would be interested in seeing the rationale for this. I hope someone from MSFT chimes in.

Regards

-Jamie