How do I make a random Item generator with no repeats?

I have a few idea's how to do this but I want to know if anyone could help me with this before.

I was thinking of using an array with each item corresponding to an x and if that x has 1 in it will spawn the item but if a 0 would choose another random until an item that has 1 in.

If someone could let me know if this is a good idea or has a better solution please let me know?

I want it to be a randomly generated item as such in binding of Isaac if that helps for reference.

For sure array is the best way to do it.

Take a look at this tutorial :

https://www.scirra.com/tutorials/315/ge ... duplicates