ruby + watir - random rather than obtain duplicate the Menu menu of elements

Test case: using a loop, random to get nine Menu menu, each must click and verify： def channel @b.goto URL channel = 0 while channel <= 8 times = rand(9).to_s AutoTest("channel_#{times}_link").click sleep 1 assert_true(AutoTest("channel_#{times}_link_on").exists?) channel += 1 end end Cycle nine times in the script, to take a random value every time, random number rand () is 0, so I element defines 0 of these nine elements of the Menu menu coding, such as: channel_0_link. But there is a problem rand () function take duplicate values​​, that some Menu menu click on 2 or more times, which our barge. I almost hunted API is not found without repeated sequentially or randomly. Next, I decided to use another random method to solve, in fact, random play is divided into two types, random and shuffle。 def channel_food @b.goto URL linkid=[0,1,2,3,4,5,6,7,8] linkid.shuffle.each{ |i| times = i AutoTest("channel_#{times}_link").click sleep 1 assert_true(AutoTest("channel_#{times}_link_on").exists?) } end The above code, can achieve randomized to get nine Menu menu, each must click and verify demand. each method is to get the data from the array; shuffle method to obtain the value of the re-arranged to use this method to do the shuffle program (does not generate repeat). a=[1,2,3,4,5,6,7,8,9] a.shuffle.each{ |i| b = i puts b }