javascript variable with apex variable error

Question

{!Account.contacts[i].Lastname}

where i is Javascript loop variable.

ERROR : Unknown property 'AccountStandardController.i'

Answer 1

I presume this is a Visualforce page.

This expression:

{!Account.contacts[i].Lastname}

is processed at the server-side where any values used such as i must exist as properties on the Apex controller. Once that processing is done, the resulting HTML is passed to the client-side (the browser) where there can also be a JavaScript variable i.

Best to think more about what you are trying to achieve keeping the server-side/client-side distinction in mind.