LUA ERROR尝试对布尔值执行算术运算

Question

  ```  local xpNeed = 100; -- E.g. 100 * lvl = XP you need to rank up!
    addEvent("onPlayerLevelUp", true);

    function addPlayerXp(player, xp)
        local acc = getPlayerAccount(player);
        local oldexp = getAccountData(acc, "exp") or 0;
        local oldlvl = getAccountData(acc, "lvl") or 1;
        local newlevel = oldlvl + 1;
        local newexp = oldexp + xp;
        lvl = getAccountData(acc, "lvl") or 0;
        if getElementData(player,'lvl') > 9 then return end
        setAccountData(acc, "exp", newexp);
        setElementData(player, "exp", newexp); 
        --if getAccountData(acc,'lvl') > 9 then return end
            if (newexp >= (oldlvl * xpNeed)) then
            local expleft = newexp - (oldlvl * xpNeed); -- added calculation for the exp that may remains after level up.
            outputChatBox("[Level-Up] Congratulations! New level "..newlevel.."!", player, 66, 134, 244);
            setAccountData(acc, "lvl", newlevel);
            setAccountData(acc, "exp", expleft);
            setElementData(player, "exp", expleft);
            setElementData(player, "lvl", newlevel);
            triggerEvent("onPlayerLevelUp", player, newlevel, oldlvl, oldexp, newexp);
        end
    end
    addEventHandler("onPlayerLogin", root, function()
        local acc = getPlayerAccount(source);
        if acc then
            setElementData(source, "lvl", getAccountData(acc, "lvl") or 0);
            setElementData(source, "exp", getAccountData(acc, "exp") or 0);
        end
    end);

    addEventHandler("onZombieGetsKilled", root, function(killer)
        if killer and getElementType(killer) == "player" then
            addPlayerXp(killer, 50);
        end
    end);

    addEventHandler("kilLDayZPlayer", root, function(killer)
        if (killer and killer ~= source and getElementType(killer) == "player") then
            addPlayerXp(killer, 50);
        end
    end);

    --[[
    addEventHandler("onPlayerSpawn", root, function(newlvl)
        if newlvl then
        if (lvl) >= 1 then
                setElementData(player, "MP5A5", 1)
            elseif lvl >= 2 then
                setElementData(player, "Tent", 1)
            elseif lvl >= 3 then
                setElementData(player, "Milk", 1)
            elseif lvl >= 4 then
                setElementData(player, "Medic Kit", 1)
            elseif lvl >= 5 then
                setElementData(player, "Shovel", 1)
            end
        end
    end);

    ]]

    table = {"Milk","MP5A5","M4A1-S","AK-47","Soda Bottle","Pizza","AS50","Tent","Medium Tent","ACR","AR-15","M107","Pasta Can","Beans Can","Golf Club"}

    addEventHandler("onPlayerSpawn", root, function(lvl)
        if not lvl then lvl = getElementData(player, "lvl") or 0; end
        if lvl >= 1 then
            for i = 1, lvl do
                setElementData(player, table[i], getElementData(player, table[i]) + 1);
            end
        end
    end);
```

[你好，这是我在这里的第一篇文章，所以我想打个招呼。因此，作为一个初学者程序员，我正在尝试为我的MTA服务器实现一个级别系统，但是，我遇到了标题中所述的障碍。这个布尔值在哪里？我该如何运作？很抱歉，这个问题似乎微不足道（确实如此），但是我真的很想前进。任何帮助将不胜感激，谢谢！

错误发生在setElementData（player，table [i]，getElementData（player，table [i]）+ 1）;我该怎么做才能使其发挥任何帮助，将不胜感激

错误70行尝试对布尔值执行算术运算和警告同一行

错误参数@ getElementData [参数1处的期望元素，为零]

Answer 1

如果您要的元素不存在，

getElementData可以返回false。我假设您希望将其视为0，所以将getElementData(player, table[i]) + 1替换为(getElementData(player, table[i]) or 0) + 1。

而且，看起来您那里没有player变量，因此它使用的是nil全局变量，因此您总是会得到nil。要解决此问题，请在local player = source处理程序的开头执行onPlayerSpawn。

Answer 2

所以我使用了您的函数，我的代码看起来像这样

   table = {"Milk","MP5A5","M4A1-S","AK-47","Soda Bottle","Pizza","AS50","Tent","Medium Tent","ACR","AR-15","M107","Pasta Can","Beans Can","Golf Club"} 

addEventHandler("onPlayerSpawn", root, function(lvl)
local player = source 
    if not lvl then lvl = getElementData(player, "lvl") or 0; end
    if lvl >= 1 then
        for i = 1, lvl do
            setElementData(player, "lvl", table[i], (getElementData(player,"lvl", table[i]) or 0) + 1);
        end
    end
end);

我添加了“ lvl” bcs prnt.sc/sc9hk1我得到了，但stil无法正常工作现在我有这个错误：https://prnt.sc/scajbc