JS中两个数组怎么比较是否相等！！

    var a = [ 1, 2 ], b = [ 1, 2 ], c = [ 1, 3 ];
    alert(a == b);//false
    alert(a == c);//false,切记不能直接比较！！

    //法一：
    alert(a.toString() == b.toString());//true
    alert(a.toString() == c.toString());//false

    //法二：运用for循环逐个比较　　　.............................