Disabling a button

Two questions:

1) How can I diable a button, so it won't be possible to press on it.
And how can I enable it again?


2) How can I change control's style after it has already been declared?


Thanks a lot guys.

1. EnableWindow.

edit:

2. SetWindowLong/SetWindowLongPtr (GWL_STYLE flag).

Is there a way to enable/disable with the control's ID, instead of handle?

>>Is there a way to enable/disable with the control's ID, instead of handle?<<

GetDlgItem

Thanks a lot