How Do I Make The Player's Mouse Lock?

I've Searched Every To Find How To Lock the Mouse So The Player Is In ThirdPerson And Has Their Mouse Locked.

UserInputServicehas a special function to change the behavior of the mouse.

MouseBehavior States:

Default:0 LockCenter:1 LockCurrentPosition:2

Code:

local UserInputService = game:GetService("UserInputService")

while true do --Loops due the CoreMenu resetting the state when you pause the game
	wait()
	UserInputService.MouseBehavior = Enum.MouseBehavior.LockCenter --Changes the behavior to 'LockCenter'
end

http://wiki.roblox.com/index.php?title=API:Class/UserInputService/MouseBehavior

I have a script that does this that I edited a while ago, you can use this (:

local player = game.Players.LocalPlayer
repeat wait() until player.Character
local char = player.Character
local hrp = char:WaitForChild("HumanoidRootPart")
local cam = game.Workspace.CurrentCamera
print("Ready")
cam.CameraType = Enum.CameraType.Scriptable
wait()
game:GetService("UserInputService").MouseBehavior = Enum.MouseBehavior.LockCenter

local x = 0
local y = 0

spawn(function()
	while true do
		game:GetService("RunService").RenderStepped:wait()
		hrp.CFrame = CFrame.new(hrp.Position) * CFrame.Angles(0, x, 0)
		cam.CoordinateFrame = hrp.CFrame * CFrame.Angles(y, 0, 0) * CFrame.new(2, 2, 12)
	end
end)

function MouseMove(name, state, inputObject)
	x = x + (-inputObject.Delta.x / 100)
	y = y + (-inputObject.Delta.y / 100)
	if y > 1.5 then
		y = 1.5
	elseif y < -1.5 then
		y = -1.5
	end
end

script.Lock.Changed:connect(function()
	if script.Lock.Value == false then
		print('Mouse Unlocked')
		game:GetService("UserInputService").MouseBehavior = Enum.MouseBehavior.Default
		--cam.CameraType = Enum.CameraType.Follow
	elseif script.Lock.Value == true then
		game:GetService("UserInputService").MouseBehavior = Enum.MouseBehavior.LockCenter
		--cam.CameraType = Enum.CameraType.Scriptable
		print('Mouse Locked')
	end 
end)

game:GetService("ContextActionService"):BindActionToInputTypes("MouseMove", MouseMove, false, Enum.UserInputType.MouseMovement)

-Just put this inside of a local script and put it in StarterPack.

-Add a BoolValue under the script and name it Lock.

-Add another LocalScript and put it under the main one and add this code

player = script.Parent.Parent.Parent
plr = game.Players.LocalPlayer
repeat wait() until plr.Character
mouse = plr:GetMouse()
local Player = plr.Character


mouse.KeyDown:connect(function(key)
	key = key:lower()
	if key == "c" then
	wait(.2)
	if plr.Backpack.MouseLock.Lock.Value == true then 
		plr.Backpack.MouseLock.Lock.Value = false
	elseif plr.Backpack.MouseLock.Lock.Value == false then 
		plr.Backpack.MouseLock.Lock.Value = true

end	
end
end)

This should work perfectly. The only bug is you won't be able to move your character freely. This is the only problem I've found with my method I've been trying to fix. I hope this helps.