how can i find value of drop down form list.

Hello all,

I want to know How to find multiple form option set value from a form.

Suppose i have an Opportunity entity and i am using three forms i.e. F1,F2....

So,when i come on opportunity form i will find an drop down through which i have to change form manually.

i am changing form on behalf of one filed on form by javascript onload method.But when i tried to switch form manually by drop down its switching automatically on previous one form F2.

how can i find value of drop down form list.