nsIDOMStorage Interface

 Retrieve an item with a given key

 @param key key to retrieve
 @returns found item or null if the key was not found

nsIDOMStorageItem getItem(in DOMString key)

 Retrieve the name of the key at a particular index.

 @param index index of the item to retrieve
 @returns the key at index
 @throws INDEX_SIZE_ERR if there is no key at that index

DOMString key(in unsigned long index)

 Remove a key and its corresponding value.

 @param key key to remove

void removeItem(in DOMString key)

 Assign a value with a key. If the key does not exist already, a new
 key is added associated with that value. If the key already exists,
 then the existing value is replaced with a new value.

 @param key key to set
 @param data data to associate with the key
 @returns found item or null if the key was not found

void setItem(in DOMString key, in DOMString data)