If you want different menu for each company create one per company and show accordingly.
If yo want to only limit what they can see, you can use SKIP FOR to control visibility of the menu items.
For a grater control over menu system, you can use free OOP Menu.

>I have a login screen for user to select ther company to login,
>I want user use different menu according to their login company.
>
>For example
>Login to company A use Menu A
>Login to company B use Menu B
>
>Menu A and Menu B is different.
>
>How to code it ?
>
>Please advise.
>
>Thanks.