Roblox, Saving Inventory.

local ItemInfo = require(script.Parent.Items)
local DataStore = game:GetService("DataStoreService"):GetDataStore("ItemsAndStats")

game.Players.PlayerAdded:connect(function(player)
    if player:WaitForDataReady() then
        game.StarterGui.ResetPlayerGuiOnSpawn = false
        print("Creating " .. player.Name .. "'s inventory.")
        local PlayerDir = game.Players:FindFirstChild(player.Name)
        local Gui = PlayerDir.PlayerGui.ScreenGui
        local MaxSlots = 28
        local CurrentSlot = 0
        local Row = 0
        local Line = 0
        local Increment = 50
        Gui.LoadingScreen.Visible = true
        local Inventory = Instance.new("IntValue",player)
        Inventory.Name = "Inventory"
        while MaxSlots > CurrentSlot do
            local GuiIncrement = UDim2.new(0,50*Row,0,50*Line)
            local BarIncrement = 14 * CurrentSlot
            if CurrentSlot < MaxSlots then
                CurrentSlot = CurrentSlot + 1
                Row = Row + 1
                local Slot = Instance.new("Frame",Gui.Inventory)
                    Slot.Name = "Slot" .. CurrentSlot
                    Slot.Size = UDim2.new(0,50,0,50)
                    Slot.Position = GuiIncrement
                    Slot.BorderSizePixel = 0
                local Item = Instance.new("IntValue",Inventory)
                    Item.Name = "Item" .. CurrentSlot
                local ItemSlot = Instance.new("IntValue",Gui.Inventory["Slot"..CurrentSlot])
                    ItemSlot.Name = "Slot"
                    ItemSlot.Value = CurrentSlot
                local ItemIdent = Instance.new("IntValue",player.Inventory["Item" .. CurrentSlot])
                    ItemIdent.Name = "Id"
                Gui.LoadingScreen.LoadingBarInner.Size = UDim2.new (0,10+BarIncrement,0,20)
                Gui.LoadingScreen.LoadingLabel.Text = "Loading: Item_" .. CurrentSlot
                if DataStore:GetAsync(player.Name .. "Item_"..CurrentSlot) then
                    if DataStore:GetAsync(player.Name .. "Item_"..CurrentSlot) >= 0 then
                                Item.Value = DataStore:GetAsync(player.Name .. "Item_"..CurrentSlot)
                        local ItemValue = Instance.new("IntValue",Gui.Inventory["Slot"..CurrentSlot])
                        ItemValue.Name = "Item"
                        ItemValue.Value = DataStore:GetAsync(player.Name .. "Item_"..CurrentSlot)
                    end
                else
                    local ItemValue = Instance.new("IntValue",Gui.Inventory["Slot"..CurrentSlot])
                        ItemValue.Name = "Item"
                        ItemValue.Value = 0
                end
                if DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot) then
                    if DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot) > 0 then
                        ItemIdent.Value = DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot)
                        local Ident = Instance.new("IntValue",Gui.Inventory["Slot"..CurrentSlot])
                        Ident.Name = "Id"
                        Ident.Value = DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot)
                        print("Loaded " .. ItemInfo[Ident.Value].Name .. " With a quantity of " .. DataStore:GetAsync(player.Name .. "Item_" .. CurrentSlot) .. " With an Id Value of " ..  DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot) .. "." )
                    else
                        ItemIdent.Value = 0
                        print("Slot " .. CurrentSlot)
                    end
                    if DataStore:GetAsync(player.Name .. "Item_" .. CurrentSlot) > 0 then
                                if DataStore:GetAsync(player.Name .. "Item_" .. CurrentSlot) > 1 then
                        local StackNumber = Instance.new("TextLabel",Gui.Inventory["Slot" .. CurrentSlot])
                            StackNumber.Name = "StackNumberLabel"
                            StackNumber.Position = UDim2.new(0,13,0,10)
                            StackNumber.FontSize = "Size8"
                            StackNumber.Text =  DataStore:GetAsync(player.Name .. "Item_" .. CurrentSlot)
                            if Inventory["Item"..CurrentSlot].Value >= 1000 and Inventory["Item"..CurrentSlot].Value <= 999999 then
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.Text = string.sub(Inventory["Item"..CurrentSlot].Value,1,1) .. "k"
                            if Inventory["Item"..CurrentSlot].Value >= 10000 then
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.Text = string.sub(Inventory["Item"..CurrentSlot].Value,1,2) .. "k"
                            end
                            if Inventory["Item"..CurrentSlot].Value >= 100000 then
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.Text = string.sub(Inventory["Item"..CurrentSlot].Value,1,3) .. "k"
                            end
                            elseif Inventory["Item"..CurrentSlot].Value >= 1000000 and Inventory["Item"..CurrentSlot].Value < 1000000000 then
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.Text = string.sub(Inventory["Item"..CurrentSlot].Value,1,1) .. "m"
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.TextColor3 = Color3.new(0, 255, 0)
                            else
                                player.PlayerGui.ScreenGui.Inventory["Slot"..CurrentSlot].StackNumberLabel.Text = Inventory["Item"..CurrentSlot].Value
                            end
                        end
                        if DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot) > 0 then
                            local Img = Instance.new("ImageButton",Gui.Inventory["Slot"..CurrentSlot])
                            Img.Size = UDim2.new(0,50,0,50)
                            Img.Image = ItemInfo[DataStore:GetAsync(player.Name .. "ItemId_" .. CurrentSlot)].UsedImage
                            Img.Name = "ItemButton"
                            Img.BorderSizePixel = 0
                        end
                    end
                end
                if Row == 4 then
                    Row = 0
                    Line = Line + 1
                end
                if CurrentSlot == MaxSlots then
                    print(player.Name .. "'s inventory has been created.")
                end
            end
            wait(0.01)
        end
    Gui.LoadingScreen.Visible = false
    Gui.ResetInventory.Visible = true
    end
end)

while true do
    for i,v in pairs (game.Players:GetPlayers()) do
        print("Saving")
        v.PlayerGui.ScreenGui.Saving.Visible = true
        v.PlayerGui.ScreenGui.Saving.Text = "Saving! This may take a while!"
        local MaxItems = 28
        local CurrentItem = 0
        while CurrentItem < MaxItems do
            CurrentItem = CurrentItem + 1
            DataStore:SetAsync(v.Name .. "Item_" .. CurrentItem, v.Inventory["Item"..CurrentItem].Value)
            if v.Inventory["Item"..CurrentItem].Value >= 1 then
                DataStore:SetAsync(v.Name .. "ItemId_" .. CurrentItem, v.Inventory["Item"..CurrentItem].Id.Value)
                print("Saved " .. ItemInfo[v.Inventory["Item"..CurrentItem].Id.Value].Name .. " With a quantity of " .. v.Inventory["Item"..CurrentItem].Value .. " and an ID Value of " .. v.Inventory["Item"..CurrentItem].Id.Value .. ".")
            else
                print("No item in Slot " .. CurrentItem)
            end
            if CurrentItem == MaxItems then
                v.PlayerGui.ScreenGui.Saving.Text = "Saved"
                wait(2)
                v.PlayerGui.ScreenGui.Saving.Visible = false
            end
        end
    end
    wait(120)
end