GetPlayerFromCharacter返回Nil-Roblox/Lua

我有一个剑术脚本,只允许npc受到伤害,而不允许玩家受到伤害。它会在任何受到伤害的npc上创建一个创建者标签。如果npc被杀,它会奖励玩家金钱(或者至少应该是这样)。我做了一些调试,发现当试图实际检索播放器时,它返回的是零。我一辈子都想不出为什么。我在谷歌上做了一些挖掘,但对我的处境没有任何帮助。

剑的脚本:

创建者标记在中创建 if humanoid.Parent ~= tool.Parent and canDamage and not game.Players:GetPlayerFromCharacter(humanoid.Parent) then 线播放器变量返回零

local tool = script.Parent
local player = game.Players:GetPlayerFromCharacter(tool.parent)

local canDamage = false
local canSwing = true

local dmg = 50
local cooldown = 1.5

local function onTouch(otherPart)

    local humanoid = otherPart.Parent:FindFirstChild("Humanoid")

    if not humanoid then 
        return 
    end

    if humanoid.Parent ~= tool.Parent and canDamage and not game.Players:GetPlayerFromCharacter(humanoid.Parent) then
        local tag = Instance.new("ObjectValue",humanoid)
        tag.Name = "creator"
        tag.Value = player
        game.Debris:AddItem(tag,0.5)
        humanoid:TakeDamage(dmg)
    else
        return
    end

    canDamage = false
end

local function slash()
    if canSwing then
        canSwing = false
        local str = Instance.new("StringValue")
        str.Name = "toolanim"
        str.Value = "Slash" 
        str.Parent = tool
        canDamage = true
        wait(cooldown) --cooldown time
        canSwing = true
    end
end

tool.Activated:Connect(slash)
tool.Handle.Touched:Connect(onTouch)