itemString Changes with API 2.0
The Item String format was changed with the release of API 2.0. Four new fields were added between enchantId and suffixID to make room for Jewel slot enchant information. Since patch 2.0.3, suffixIDs and uniqueID's can be negative which indicates the scaling factor of the negative random suffix's bonuses (see the Scaled Random Suffixes section below and the ItemRandomSuffix section).
itemString API TYPE (String)
Item strings are used in World of Warcrafts chat interface to pass item information in item hyperlinks between clients and to pass item information from the client to the user interface. The main purpose of an item string appears to be to designate display information of item tooltips via item hyperlinks (itemLinks).
Item String Formatting
Item strings consist of 8 numerical values in a common format. The eight numerical values define an item's name and base stats (ItemId), any enchants that are applied to the item (EnchantId), any jewel socket enchants(jewelId1-jewelId4), any extra item stats ("of" type items)(SuffixId), and finally a unique identifier for the item for created items or quest rewards (UniqueId).
item:itemId:enchantId:jewelId1:jewelId2:jewelId3:jewelId4:suffixId:uniqueId
You can extract these identifiers from a given itemString with the following LUA-code:
local found, _, itemId, enchantId, jewelId1, jewelId2, jewelId3, jewelId4, suffixId, uniqueId = string.find(itemString, "^item:(%d+):(%d+):(%d+):(%d+):(%d+):(%d+):(%-?%d+):(%-?%d+)")
"%d+" matches a positive integer while "%-?%d+" matches a positive or negative integer. See HOWTO: Use Pattern Matching for information.
Enchant Ids and Suffix Ids
Adding of enchant, jewel, and bonus stat information to the tooltip appear to be handled on the client side with out any kind of validation. By altering the item string in an item hyperlink you can add any enchant or any bonus stats to any item and still pass it to clients via chat, or display a tooltip for it. The Item name must match that of the itemId combined with the suffix or you will be disconnected if you try to link the item to others. suffixIDs can be negative (see Scaled Random Suffixes below).
- Full list of EnchantIds.
- Full list of SuffixIds.
Unique Ids
UniqueIds don't appear to hold any information in and of themselves, and are not consistant in any way across servers like enchantIds and secondaryIds. This number appears to only be a link to data held on the server or client that returns information about who the item was created by or for. In the case of items recieved from quests, these seem to be considered made for the player who receives them, and thus gets a uniqueId even though no extra tooltip information is displayed. It also seems that uniqueIds are somewhat pointless to include in the item string passed to the client as uniqueId information can only be seen on items that are actually on a person where item strings aren't used to set the tooltip; for item hyperlinks, uniqueId information is ignored. uniqueIDs can be negative (see Scaled Random Suffixes below).
Scaled Random Suffixes
Since WoW 2.0, both the SuffixIds and the UniqueIds have the ability to be negative. This indicates a different way of calculating the stats bonuses is being used. Previous to WoW 2.0, every time a new stats bonus was added to a new item, the SuffixId list needed to be updated via a client patch. This limited Blizzard's ability to arbitrarily add new items to the game, since the new data would need to be accompanied by a client patch if it's stats bonus did not already exist.
Post 2.0, a new system of stats bonuses has been implemented via the ItemRandomSuffix table. If the suffixId is negative, it indicates that the suffix of the item is instead one of the new RandomSuffixes, and that the uniqueId will contain an embedded suffixFactor, which can be extracted via the following algorithm.
local suffixFactor = 0
local linkType, itemId, enchantId,
jewelId1, jewelId2, jewelId3, jewelId4,
suffixId, uniqueId = strsplit(":", itemString)
suffixId = tonumber(suffixId) or 0
uniqueId = tonumber(uniqueId) or 0
if (linkType == 'item') then
if (suffixId < 0) then
suffixFactor = bit.band(uniqueId, 65535)
end
end
To see how this suffixFactor gets applied to get the final stat bonuses, see the ItemRandomSuffix table.
Jewel Ids
The jewelId fields seem to be accepting the same values as the enchantId fields. So in fact any enchantId can be used as jewelId. The gem icon only shows up at some Ids though.
Example Item Strings
"item:6948:0:0:0:0:0:0:0"
- The first number is the ItemID for a [Hearthstone]. The other 7 values are 0, which tells the client it has no enchants, extra stats, and wasn't made by anyone.
"item:18832:2564:0:0:0:0:0:0"
- The first number is the ItemID for [Brutality Blade]. The second number (enchantId) in this case denotes that it is enchanted with +15 agility.
"item:10242:0:0:0:0:0:614:0"
- The first number is the ItemID for [Heavy Lamellar Gauntlets]. The seventh number (suffixId) adds to this item's name " of the Monkey" and adds +11 Agility and +11 Stamina.
"item:4388:0:0:0:0:0:0:210677200"
- The first number is the ItemID for [Discombobulator Ray]. The eighth number adds the information that this particular item only has 4 uses left and was made by Kirov.
"item:28484:1503:0:2946:2945:0:0:0"
- The first number is the ItemID for [Bulwark of Kings]. The second number (enchantId) is that of +100 HP. The third number denotes an empty blue jewel socket while the fourth and fifth numbers represent yellow jewel sockets occupied by a [Inscribed Ornate Topaz] and a [Bold Ornate Ruby] respectively. Jewel sockets can also take normal enchantID's. Bulwark of Kings has a socket bonus, but this is not represented within the itemString.
Note: The eighth number does not always stand for who made an item; it usually appears on quest items too, and sometimes on dropped items. It's possible that the value is a reference to a database entry which can hold extra data, such as who made an item, which quest it came from, when the quest was delivered, who sold the item on the Auction House, etc. etc. GMs would then be able to track an item should a petition about one be made.