Hi Robin,

I do not know of a way to stop excel evaluating a formula as it is entered
(apart from fill which I do not think will help you).

Some ideas for exiting the UDF when it is you inserting it:

if application.caller.formula="" then exit function

or

if application.caller.formula like "=*Myfunc(*)*" then exit function

or put a hidden name in the workbook =true when you are inserting and =false
after you have inserted, and check that in the function.

Charles
______________________
Decision Models
FastExcel Version 2 now available.
www.DecisionModels.com

"Robin Hammond" wrote in message
...
Here's the problem...

Main routine does this

1. sets calculation to manual, saving old calc state (usually auto)
2. Loops through a region inserting a User Defined Function either cell by
cell as a formula or range by range as an array formula
3. Even though calculation is set to manual, on each insert the UDF
triggers
and calculates even though I don't want it to.
4. The UDF is hitting a web server to return a value from a database and
is
not the quickest thing in the world. It's pretty cool though.
5. Routine completes (slowly because of all the calculations as it goes)
6. Calculation is reset to its old state, and if this was automatic, the
udf
then recalculates all the values even though the udf is not flagged as
volatile and nothing else has changed. If it was manual, I could of course
recalculate at this stage if I needed to.

One problem is that the UDF is in a different addin so I cannot run a
public
variable and use this as a get out clause when the UDF triggers.

Any ideas anybody on how I can really turn calculation off or restructure
this to avoid a double calculation loop.

Thanks as always,

Robin Hammond
www.enhanceddatasystems.com