指令樓

第一部分

execute @e[name=§l§e彈夾] ~~~ tag @p add q

replaceitem entity @a[tag=q] slot.hotbar 0 iron_nugget 30 0 {"minecraft:item_lock":{"mode":"lock_in_slot"}}

execute @a[hasitem={item=iron_nugget,quantity=0}] ~~~ tag @p remove q

kill @e[name=§l§e彈夾]

第二部分

replaceitem entity @a[tag=!q] slot.hotbar 0 barrier 1 0 {"minecraft:item_lock":{"mode":"lock_in_slot"}}