Getting the Length of A Multidimensional Array

Hi i  all i need a bit of help

how do you get the length of a specfic dimension in a mulit dimensional array// for example if i had a 3 dimensional array (x,y,z) - storing ID ( all integers)

how would i get the length of the dimension z when x = 1 and when y = 1- --- note in my array the length of z varies for example when x = 2 and when y =3 there are 10 z values - which all store 10 unique numbers- using getLength would return the largest length of Z eg 20

- by the way i am using visual web developer 2008 express

 

thank you so much for your help in advance// please note that i am using visual basic and that i am just a beginner in programming - by the way how do you add diagrams in a post> !
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