TOPIC:

Hi,

How do we check for an empty value (no value defined) for the Virtuemart product packaging field of a product ?

We are writing a rule that uses the TotalPackaging field in a calculation for working out shipping charges for the total order for Express Postage. (We are using the Advanced Shipping Rules)

But I need a rule that excludes this shipping method if the order contains any products where we haven't defined the Virtuemart "Product Packaging" size for a product. (We have so many products, we haven't got around to defining package size for each of them and also want to cautious if we forget to populate the field when adding new products, would like to exclude it from our express post shipping rule)

Tried using a rule like below hoping that MinPackaging==0 would catch a product with empty product packaging value but didn't work.

---

Name=Product weight NOT defined; MinPackaging==0;NoShipping
Name=Express Post; ShippingWithTax=TotalPackaging*5.00

Appreciate any assistance, thank you.

Dear ShopOfToys,
Unfortunately, there is currently no way I'm aware to check whether a field is defined at all. In PHP, internally it has a value of Null, but the plugin does not have that value implemented, so you can't check for Null (becuase "Null" would be a string and Null without quotes would be interpreted as a variable that does not exist).

The only way I can think of is that you implement a custom plugin to extend the shipping by rules plugin: open-tools.net/virtuemart/advanced-shipp...ipping-by-rules.html

The last section on that page documents the API, the first few plugins can be used as sample code for implementation.
In such a custom plugin you have full access to the whole cart data structure in PHP, so you can loop through all products in the cart and check whether product packaging has a value set or not. If not,you can e.g. set a custom variable that you use in your rules to exclude the order from shipping and print out a warning.

Sorry that I can't provide an easier way....

Best regards,
Reinhold

Thanks Reinhold for looking into this and your response.

For now, think we have worked around it okay by checking MinPackaging < 0.0001

Can understand the complexity in checking for the Null value.

Problem solved.