Reading Value Of Field In Child

Hi,

I’m trying to read the value of a form field in a child from the parent.

The child window is created in an iframe, called ‘transx’.
The field within the child window is called ‘tx’.

From the parent, I want to read that field value.
I have tried the following, none of which work;

var trx = top.content.cart.transx.tx.value; (yes… child, grandchild and great grandchild… no comments please, it is necessary for this application)
var trx = transx.tx.value;
var trx = transx.document.getElementById(‘tx’).value;
var trx = transx.getElementById(‘tx’).value;

I think I’ve run out of plausible variations.

Any suggestions?

Thanks
CTB

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