Fixed game resolution

Hello,
My game default resolution is 700x500 in the webplayer. I want this resolution to be fixed, in case of changing resolution, the game not be started. How can I do this?

How about this?:

Vector2 targetResolution;

void Start()
    {
    targetResolution = new Vector2(700, 500);
    }

Update()
    {
    if(Screen.width != (int)targetResolution || Screen.height != (int)targetResolution)
        {
        //WRITE GUI MESSAGE HERE AND QUIT GAME [or whatever you want to do]
        //Do something like... Application.Quit();
        }
    }