application.onkey depending on a if function.

Dear excel friends,

My challenge is to find out the following:

Sub exam.()
if Sheets("Sheet1").protect=true Then
application.OnKey "{DELETE}","key"
end if
end sub

and

Sub key()
ActiveSheet.Unprotect ("password")
end sub

does the "application OnKey" works as well depending on an if function? In case the sheet is unprotected, the delete button should be used to clear the cell contents.

Hope you can help me out.

kind regards,